The Alpine Gardener - December 2015

342 THE ALPINE GARDENER

Alpine Gardener the

JOURNAL OF THE ALPINE GARDEN SOCIETY

VOL. 83 No. 4 DECEMBER 2015 pp. 352-467

the international society for the cultivation, conservation and exploration of alpine and rock garden plants

Volume 83 No. 4

December 2015

Alpine Gardener THE

364

CONTENTS 353 EDITOR’S LETTER 355 ALPINE DIARY

A round-up of AGS shows in 2015; book review.

364 ROBERT ROLFE’S DIARY A look at oriental highlights throughout Britain in the past year.

396 PHOTO ALBUM:

MEDITERRANEAN ISLANDS

A mouth-watering selection of images from the AGS Slide Library.

408 ALPINE BRASSICAS

408 444

There can hardly be an AGS member who does not grow at least one alpine brassica, whether it be Iberis or Draba.

Robert Rolfe assesses their current status in cultivation.

444 PATAGONIAN BRASSICAS

Martin and Anna-Liisa Sheader choose the best.

452 THE ENIGMA OF A SCOTTISH WILLOW

David Tennant researches the mysterious origins of Salix x boydii.

December 2015 Volume 83 No 4

PRACTICAL GARDENING

374 DAPHNE PETRAEA Robin White passes on his expertise in growing the finest forms of this very desirable dwarf shrub.

374

386 SHRUBS ON SANDY SOILS

Vic Aspland copes with cultivation on ‘beach-like’ soil.

458 PRIZE PLANTS

Splendid exhibits from this year’s Ulster, London, East Anglia, Malvern, Southport, Wimborne, Bakewell and Pershore AGS shows.

COVER PHOTOGRAPHS

FRONT Ophrys speculum from Bulbs

of the Eastern Mediterranean by Oron Peri, just published by the AGS (Nejdet Bozkut).

BACK Epipactis veratrifolia near Episkopi, Cyprus (Peter Sheasby; see page 396).

ON THESE PAGES

LEFT Trillium grandiflorum f. roseum;

Heliophila coronopifolia with Cotula turbinata; Sarcodrabra subterranea.

RIGHT Daphne petraea ‘Cima Tombea’; Serapias neglecta; Delosperma ecklonis ‘Fire Spinner’ shown by Audrey Dart at this year’s AGS East Anglia Show.

396 458

Published by the

Alpine Garden Society

The international society for the cultivation, conservation and exploration of alpine and rock garden plants, small hardy herbaceous plants, hardy and half-hardy bulbs, hardy ferns and small shrubs AGS Centre, Avon Bank, Pershore, Worcestershire WR10 3JP, UK Tel: +44(0)1386 554790 Fax: +44(0)1386 554801 Email: ags@alpinegardensociety.net Director of the Alpine Garden Society: Christine McGregor Registered charity No. 207478 Annual subscriptions: Single (UK and Ireland) £33* Family (two people at same address) £37* Junior (under 18/student) £15 Overseas single US$56 £35 Overseas family US$62 £38 * £2 deduction for direct debit subscribers Printed by Buxton Press, Palace Road, Buxton, Derbyshire SK17 6AE. Price to non-members £8.00 Second-class postage paid at Rahway, New Jersey.

US Postmaster: send address corrections to AGS Bulletin, c/o Mercury Airfreight International Ltd. Inc., 2323 Randolph Avenue, Avenel, NJ 07001. USPS 450-210.

Editor: John Fitzpatrick Tel: +44(0)1981 580134 Email: editor@agsgroups.org Associate Editor: Robert Rolfe Tel: +44(0)1159 231928 Email: robert.rolfe@agsgroups.org Practical Gardening Correspondent: Vic Aspland CChem. MRSC Tel: +44(0)1384 396331 Email: vic.aspland@agsgroups.org Custodian AGS Slide Library: Peter Sheasby Tel/fax: +44(0)1295 720502 To advertise in The Alpine Gardener please call or email the AGS Centre (details above) The Editor welcomes contributions of articles and photographs. Please call or email the Editor to discuss relevant formats for photographs before sending. The Editor cannot accept responsibility for loss of, or damage to, articles, artwork or photographs sent by post.

The views expressed in The Alpine Gardener do not necessarily reflect those of the Editor or of the Alpine Garden Society. The Alpine Gardener is published four times a year in March, June, September and December.

© The Alpine Garden Society 2015 ISSN 1475-0449

www.alpinegardensociety.net

MIKE IRELAND

Onosma frutescens in the Greek islands (see AGS Slide Library feature on page 396)

T

hank you to all the members who responded to my Editor’s Letter in the last issue of The Alpine Gardener, which concerned the number of non-members in AGS local groups.

You put forward a wide range of views, from those who felt I had ‘attacked’ local groups to those who were ‘horrified’ that AGS groups had even a single nonmember among their ranks.

I can assure members that it was never my intention to ‘attack’ groups, merely to point out a breakdown in co-operation between groups and the parent body, a widespread breach of the AGS Constitution (groups were permitted to recruit 25 per cent nonmembers but it had become clear that many had substantially more than that) and some of the possible consequences.

DECEMBER 2015

AGS groups: a new way forward Editor ’s letter All the responses I received were put before the AGS Trustee Board at its meeting in October. The trustees decided to abolish the restriction on non-members in groups. This means that groups are now free to recruit as many non-members as they wish. Also, groups are fully covered by the AGS insurance since all now comply with 353

EDITOR’S LETTER the Constitution. In return, the trustees have asked that all groups should return their accounts and membership lists to the AGS Centre each year and make a contribution towards the cost of the insurance. Letters giving details have been sent to all group secretaries.

It is hoped that this decision will encourage a more co-operative and mutually beneficial relationship between the groups and the parent Society to ensure a flourishing and long-term future for the AGS.

I

have been contacted by Marek Slovak, a botanist who works in the Department of Vascular Plant Taxonomy at the Institute of Botany of the Slovak Academy of Sciences in Bratislava, Slovakia.

Marek is involved in an evolutionary and taxonomic study of the genus Soldanella. He writes: ‘We study members of this genus using the most modern and sophisticated molecular genetic analysis. In order to determine evolutionary relationships, we need to analyse samples of closely related genera, in particular Hottonia, Omphalogramma and Bryocarpum. We can easily obtain samples of Hottonia but unfortunately this is not the case for the other two genera. I have approached various botanic gardens, including Kew, to ask for samples but have been unsuccessful so far.

‘I wonder if any members of the Alpine Garden Society possess any specimens of Omphalogramma or Bryocarpum and, if so, would be kind enough to provide me with samples for molecular analyses.

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I require one to two intact leaves from each plant, dried in silica gel. Leaves must be dried in the gel immediately after they are collected.’

If you can help, or for more information, please contact Marek by email at marek. slovak@savba.sk

I

n 2011 I wrote in this column about Doris Punchard, who had decided to step down as an AGS member on reaching her 107th birthday. She had been a member for almost 50 years and was a founder member of the Suffolk local group, which was set up around 1960.

Sadly ‘Punch’, as she was affectionately known, died on August 12 this year at the remarkable age of 111, the sixth oldest person in the UK at the time.

Jeremy Pratt, a former secretary of the group, recalls: ‘She continued to come to local meetings until she became too unsteady on her feet in 2011, and remained enthusiastic and knowledgeable about alpine plants, with a wry sense of humour.’ If ever there was evidence that alpine gardening is good for you, it is surely Doris’s longevity. She will be sadly missed.

John Fitzpatrick  We’d like to hear your views about articles in The Alpine Gardener, and also about your experiences of growing plants or searching for them in the wild.

Please write to the Editor at the AGS Centre (address on title page) or email editor@agsgroups.org.

THE ALPINE GARDENER

ALPINE DIARY DOUG JOYCE

Colourful and packed benches at the Kent Show in March

T

hose who have regularly attended AGS Shows for many years will have memories of any number of highlights, but will surely agree that 2015 was as good as any, with plants that were not even in cultivation until fairly recently now grown to the very highest standards.

On the one hand the number of people sending back seed from the wild has clearly decreased; on the other we seem to be getting better at maintaining recent introductions, and onetime supposedly impossible or little-known species are now firmly established.

Only a few show venues have remained unchanged over the years, the majority shifting within their county or migrating further afield. We salute David Hoare, who retires after a lengthy stint running

DECEMBER 2015

Exhibitors put on a great show of skill 2015 SHOWS ROUND-UP both the spring and autumn Kent shows at Rainham, which will now transfer to Sutton Valence with Adrian Cooper in charge.

The high summer show reverted to its former Pershore locale, this time in a giant glasshouse that had only a few weeks earlier been filled with summer bedding plants. There was plenty of 355

ALPINE DIARY DOUG JOYCE

Judges at work: Ray Drew, Cecilia Coller and Christopher Brickell

space for the substantial entry, and the college’s home-produced apple and pear juice was welcome on a rather warm day when temperatures soared under cover, despite the provision of shading and industrial fans.

Later, in October, the Newcastle Show was held at a garden centre in Woolsington, which marked a successful transfer from its previous Ponteland venue. And all who went the following week to the last show of the year, held at RHS Garden Harlow Carr, just outside Harrogate, were impressed by Eric Rainford’s deft handling of the event, by the co-operation of the garden’s staff (a tour of the alpine house was laid on), and by the spectacular backdrop of the garden itself, shimmering in full autumn 356

display on a day when the weather could hardly have been better.

For many years the Alpine Garden Society has held an April Show at one or other of the RHS Westminster Halls, and for the past two it has participated in a Sunday show. On this occasion the London Marathon clashed with the event and there were fears that this would hamper the best efforts of exhibitors – happily unfounded, for this part of the capital was little affected and a very creditable display was achieved.

The RHS has decided to remove this event from its calendar of London shows and as a result has withdrawn use of the venue. The alternative offered for 2016 was a two-day midweek show in a tent at Wisley and this was not attractive THE ALPINE GARDENER

DOUG JOYCE

ROBERT ROLFE

The busy plant sales area at the Harlow Early Spring Show

DECEMBER 2015

DOUG JOYCE

to our exhibitors, so there will be no London Show next year. The Malvern Show will also be dropped because the AGS is no longer able to meet the organiser’s requirement of filling the large exhibition hall for four days.

It is difficult to highlight one show in particular for an outstanding display this year, but all who went on Easter Saturday to Stockton Sixth Form College for the Cleveland Show were dazzled by the large number of beautifully grown, mature plants on the benches. This was one of the first occasions when the new class for a pan ‘planted as a miniature alpine landscape’ was trialled, and the acting Director of Shows, who had travelled up from Hampshire for the occasion, had her work cut out patiently

Edward Spencer wins his first Farrer Medal at Pershore (see also page 467) 357

ALPINE DIARY DOUG JOYCE

The London Show, which was held in April, will not take place next year

explaining the ethos of this innovation to the judges, whose views concerning the various accessories used were decidedly mixed. That said, it was well-supported class and much enjoyed by visitors.

In 2015 the total number of plant entries (including multi-pan classes) was 7,635, with a total of 10,495 plants staged, a slight drop on last year. The most plants, 687, were put on the bench at Chesterfield, followed by Northumberland with 645 and Midland with 627. The average was 437 plants per show. The Loughborough spring event attracted the highest number of exhibitors at 78, but this was down 15 on last year. The average was 46 exhibitors per show.

Two exhibitors won their first Farrer 358

Medals this year: Peter Furneaux at Loughborough with Narcissus ‘Mitzy’ and Edward Spencer at Pershore with Campanula fragilis. During the year three Gold Medals were awarded to plant exhibitors, as well as seven Silver and nine Bronze.

In distant years the shows, far fewer in number, didn’t start until mid-March and finished by the end of September.

As the range of alpine plants grown has broadened, it is as well that the span is now mid-February to mid-October.

A dedicated exhibitor’s life is one of unremitting effort, ridiculously early morning starts, occasional bemusement at judges’ decisions, friendly rivalry and moments of elation that make the whole slog worthwhile.

THE ALPINE GARDENER

ALPINE DIARY

AGS AGGREGATE SHOW RESULTS 2015

OPEN SECTION TOP TEN 1 2 3 4 5 6 7 8 9 10

First First Second Third places points * points points Don Peace, Yarm 144 252 69 26 Bob & Rannveig Wallis, Carmarthen 61 171 38 53 Ivor Betteridge, Ashby-de-la-Zouch 77 149 75 32 Lee & Julie Martin, Pevensey 64 116 48 19 Paul & Gill Ranson, Chippenham 54 114 61 28 Alan Newton, Ponteland 47 80 85 37 Alan & Janet Cook, Dinton 56 77 48 36 Mavis & Sam Lloyd, Redditch 38 60 51 42 Ian Kidman, Ebchester 30 58 13 8 Geoff Rollinson, Holmfirth 29 55 10 5

INTERMEDIATE SECTION TOP FIVE 1 2 3 4 5

Bob Worsley, Woodford Pauline Carless, Redditch Steve Walters, Shelley Norman Davies, Bacup Lawrence Peet, Harrogate

85 42 43 33 18

145 58 57 37 33

69 116 27 28 17

46 75 6 24 22

12 16 9 7 8

16 16 9 9 8

10 7 3 0 6

7 2 1 0 1

NOVICE SECTION TOP FIVE 1 2 3 4 5

Janet Fielden, Appleby Mark Lee, Beeston Adam Bramley, Chesterfield Vivien Self, Maiden Law Elizabeth Ross, Co. Westmeath

ARTISTIC SECTIONS PHOTOGRAPHIC OPEN 1 Jon Evans, Farnham 43 98 73 38 2 Joan & Liam McCaughey, Ballinderry 29 63 73 41 PHOTOGRAPHIC INTERMEDIATE 1 John Hill, Worcester 27 47 25 8 2 Chris Oatway, Newby Bridge 8 18 3 4 PAINTINGS/DRAWINGS/NEEDLEWORK OPEN 1 Jean Morris, Berkhamsted 39 81 27 3 2 Rannveig Wallis, Carmarthen 24 48 8 0 PAINTINGS/DRAWINGS/NEEDLEWORK INTERMEDIATE 1 Vincent Daniels, Woodford Green 30 36 8 0 2 Maeve Spotswood, Bray 4 4 3 0 * First, second and third points are awarded for each plant exhibited. For example, a first place in a three-pan class is awarded three first points.

DECEMBER 2015

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S

teppes are semi-arid habitats (25 to 50cm of rainfall annually) experiencing great extremes of temperature. They are rich in biodiversity and characterised by grasses and grasslike plants but also sustain a great array of other herbaceous species.

Steppes are found in Central Asia, North America, Patagonia and South Africa and are the subject of this interesting new book produced by Denver Botanic Gardens.

The concept behind the work is to explore steppe ecologies as a context for a further examination of the plants, particularly those of aesthetic value, which they support. In addition to drawing attention to the various threats which imperil these important ecosystems, part of the rationale of the book is to attempt to identify which of the plants under scrutiny might become of use horticulturally as climate change makes extreme weather events more common, prompting a demand for resilient species. The foreword explains that this effort is co-ordinated though the collaborative Plant Select programme but I looked in vain for a fuller explanation of this scheme.

The book begins with a brisk, efficient and accessible introduction giving details of the climate, geology and soils common to steppe biomes. A floristic comparison of steppe plant communities nicely sets the scene for what follows.

There are five steppes in total (those of North America being split between the Central and Intermountain steppes).

These are dealt with in turn, each by a different author. Each area is introduced 360

Searching the steppes for garden plants BOOK REVIEW Steppes: The plants and ecology of the world’s semiarid regions,

by Michael Bone, Dan Johnson, Panayoti Kelaidis, Mike Kintgen and Larry G. Vickerman. Published

by Timber Press. Price £35. ISBN 9781604694659

briefly followed by notes on the region and the features it includes. The material covered is not uniform but is appropriate and of interest, tending to address aspects of climate and geology, often with a focus on human interactions with the plant life.

The second part of each treatment is devoted to a section called ‘Plant Primer’ where the plants of the area are considered more closely. The text is arranged according to family with the various species addressed in an anecdotal, somewhat uneven way. This THE ALPINE GARDENER

BOOK REVIEW

Convolvulus tragacanthoides in Kazakhstan, from Steppes

may be frustrating for gardeners as, though the genera are usually discussed in alphabetical order, the names can be difficult to pick out and the information provided about the plants is variable.

A possible improvement might have been to include a more structured encyclopedic element.

In the first treatment on Central Asia, Michael Bone, Curator of the Steppe Collection at Denver, is careful to associate the wild plants with their cultivated relatives, which adds much to his account. Elsewhere, though, DECEMBER 2015

there is often surprisingly little advice on how the plants featured might be cultivated or used horticulturally or whether they are even obtainable by the domestic gardener. Nevertheless, there is still much for the armchair traveller to enjoy. The plants are fascinating and the writing engaging and well-paced throughout.

As might be expected, some of the images used to illustrate the various plants and habitats are spectacular.

However, there are a number of out-offocus pictures, which seems unnecessary 361

ALPINE DIARY

Allium platycaule, from North America’s Intermountain steppe, does well in gardens

Acantholimon alatavicum in alpine steppe, Pakistan 362

THE ALPINE GARDENER

BOOK REVIEW

Gladiolus dalenii in South Africa’s Eastern Cape – a striking image from Steppes

given the ease of digital photography and the photogeneity of the subject matter.

With the conclusion of the treatment of the South African steppe the book ends rather abruptly and some final remarks drawing together what has gone before might have been helpful. Planting lists with recommendations for garden use would make a further useful addition.

This book is an interesting attempt to marry a study of an important ecology type and an assessment of the horticultural potential of the botanical biodiversity it nourishes. To an extent it might be argued that in its wide remit it fails to be one thing or another – neither an academic treatise nor a horticultural reference work. However, within the breadth of its content there is plenty to hold the attention of those who love wild DECEMBER 2015

places and the challenge of cultivating the strange and beautiful plant life found in them. The work brings together a fund of information and succeeds in its purpose of demonstrating the largely untapped horticultural value of these harsh landscapes, both now and in the future. This is an ambitious project and it is encouraging to see a botanic garden tackling interpretive work of this nature and on this scale.

James Armitage  Steppes is available to AGS members at £28, a discount of 20 per cent off the published price. To order visit our online book shop or use the order form in the issue of AGS News that accompanies this journal.

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ALPINE DIARY

Robert Rolfe’s Diary

‘W

omen are bloody awful painters. Don’t ask me why; they just are.’ This sweeping pronouncement suggests that the mischievous critic who delivered it was as much myopic as misogynistic. He clearly didn’t take into account botanical illustrators and artists, many of the finest of whom happen to be female.

Many readers will be familiar with Kit Grey-Wilson’s field guide The Alpine Flowers of Britain and Europe, the 1,500plus colour illustrations provided by Marjorie Blamey, a remarkably prolific exponent of this discipline. There are numerous other dazzlingly gifted practitioners from the present and the living-memory past – Lilian Snelling, for example, whose first commission, a century ago, was to paint at Colesbourne for Henry Elwes; Coral Guest; Kathy Pickles; Kew-linked Christabel King, Ann Farrer, Joanna Langhorn and Pandora Sellars; Japanese Mariko Imai; and my favourite of all, Germanborn Regine Hagedorn, who transfers the intricate skills of a jeweller (her other speciality) to create studies of breathtaking precision and sheer beauty.

A number within our Society are lucky enough to have paintings by such virtuosos hanging on their walls.

Even I (a very minor collector indeed) occasionally receive emailed catalogues from picture dealers who misjudge the breadth of my wallet and the extent of my extravagance. One recent cornucopia

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An oriental reflection on the year just gone included a cache of paintings from the estate of two sisters, representing the work of an AGS member who died in September, Yorkshireman Raymond Booth. He too was, indeed is renowned worldwide for his oil-on-paper interpretations of flowers and fauna, particularly butterflies and birds.

The collection, sold in late November, included ‘Red admiral and hawthorns’, ‘Robin on a birch tree’ (my token seasonal offering) and a cheering typing error, ‘Iris and corn studies’, the clone in question almost certainly Iris histrioides ‘Lady Beatrix Stanley’ with its flowers and corms (not ‘corns’) meticulously depicted. Outdoors, the ‘noses’ of this were poking through the grit here in Nottinghamshire by the third week in October – earlier than in any other year I can recollect, so the pot was brought under glass to foil the voles and molluscs that treat them as bonnes bouches.

Other notable works by Booth include a clump of Meconopsis overlooked by THE ALPINE GARDENER

ROBERT ROLFE

Crocus speciosus ‘Oxonian’ is said to breed true if kept isolated from its cousins

Magnolia wilsonii, ‘Collared doves in Sorbus ‘Joseph Rock’ (which sold at Christie’s five years ago for more than twice the upper estimate), and ‘Autumn crocus’ (Crocus speciosus and Colchicum speciosum ‘Album’ with pale pink Hesperantha coccinea, a windfall apple and a blackbird poised to peck it). This I covet but cannot have.

Instead I enjoy to the full a first-rate selection of ‘Oxonian’, the Crocus which has flowers as violet-blue as any reticulate DECEMBER 2015

Iris, is easily substantial enough to be interplanted with the Colchicum and apparently breeds true if kept isolated.

My original stock has spread around slowly, its distinctive, dark-tubed flowers peeking out from the skirts of Hypericum olympicum, amid and on the fringes of massed Eryngium bourgatii and close to equally spiny Dianthus ‘Eileen Lever’, where its seeds (rather than cormlets) have presumably lodged and found a protector. No other representatives of 365

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Aster trifoliatus subsp. ageratoides var. alpinus is just 20cm tall

the species are present, so this Oxford Blue veteran remains ‘pure’. To bolster the representation, a further 40 were ordered in the summer from the same source as their predecessors. Imported corms supplied by this nursery came 100 per cent true.

It would be ridiculous to speak of Raymond Booth without mentioning that inspired collaboration with Don Elick, Japonica Magnifica (1992), in which 85 of his most accomplished paintings are showcased. More affordable than any of his four-figure originals, it nonetheless constitutes a pricey purchase, aimed at the connoisseur, the bibliophile and custodians of reference libraries.

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The authors were spoilt for choice regarding subject matter: Japan is home to approximately 5,600 species of vascular plants, just over a third of them endemic. I’ve encountered quite a few in British gardens over the course of the year. For example, there’s a very useful dwarf Aster from Honshu that in its dwarfest form, A. trifoliatus subsp. ageratoides var. alpinus, can be just 20cm tall, with masses of small flowers that fade from mid to palest blue or white by the time the earliest Michaelmas daisies are in bloom, as such doing sterling service from late July onwards. Sometimes grown under the synonym A. viscidulus var. alpinus, it has undergone several name changes THE ALPINE GARDENER

ROBERT ROLFE

Viola brevistipulata var. hidakana can flower from April to August in the UK

that have perhaps put those wishing to acquire it off the scent.

Memorising Latin plant names defeats some gardeners. While gifted when it comes to getting to grips with a spade or secateurs, they find it difficult to grasp the nomenclatural aspects of horticulture. For others, me included, it’s the more outlandish cultivar names that are unmemorable and unappealing.

The more ‘inventive’ and whimsical the coining, the more it grates. Sticking with Japanese plants, there are several likeable dwarf hostas, yet names such as ‘Teenyweeny Bikini’ are difficult to stomach.

Similarly, I greatly like the genus Viola in numerous of its guises, yet would baulk at growing something DECEMBER 2015

called ‘Frilly Dilly’ from the twee name alone, though its appearance didn’t thrill me either when seen in a ‘Plant of the Year’ competition. There might be uncertainty concerning the validity of the taxon V. brevistipulata, according to that arbiter of currently accepted usage, The Plant List. Yet the name was good enough for Viola guru Wilhelm Becker and for Dr Jisaburō Ohwi, who compiled the standard Flora of Japan, its English translation published in 1965.

My admiration dates from 45 years ago when I saw V. brevistipulata in a peat garden (most self-respecting British rock gardens had one back then).

The alpine variant hidakana, from Hokkaido, is at present offered by a 367

ALPINE DIARY couple of nurseries and gives promise of finally settling down with me, for it has self-sown this year and last. The main burst of flowers comes in early April but a succession can be expected through to July or even August if the compost – gritty, humus-rich and lime-free – is kept moist and shade is provided.

Otherwise it dies down in high summer.

It is cleistogamous, which describes the trait of certain plants to self-pollinate unopened flowers later in the season. To harvest the seed, the trick is to inspect the seed pods in the morning, before they thrust open in warmer temperatures and send their seeds rocketing up to a metre from the capsule launch pad. These will germinate even in August or September but the snag is that such latecomers scarcely have time to form substantial plantlets before colder weather induces dormancy or leads to infant mortality.

You might instead choose to divide the creeping rhizomes in early spring, when re-establishment is quickest. All plants are variations on a fairly constant theme but some have markedly larger, broaderpetalled flowers. One Japanese picture book recognises four subdivisions – f. ciliata, f. incisa, f. glabra and f. parviflora – based on foliage and only in the last case floral characteristics, from the central and western parts of Hokkaido, a mountainous, northerly island. The thick-textured, glossy leaves, blackish stems and dark-veined, deep yellow flowers are common to all.

Now a disparate switch, from a bona fide dwarf alpine to Akebia quinata, a climber that can reach up to 6m at full throttle (half that height is more typical if domesticated) in China, Korea and 368

Japan from Honshu southwards, where the aforementioned Ohwi described it as ‘common’ in ‘thickets in hills and mountains’. It looks impossibly exotic, rather like a hothouse Hoya (another genus that has a toehold in Japan) impossibly crossed with a Hydrangealike Deinanthe or a staminode-centred Clematis, mid purplish-pink with darker central structures. Several other colour forms are available, among which ‘White Chocolate’ has an Award of Garden Merit, and ‘Amethyst Glow’ is well worth having. The Akebia I saw, in the second week of May, was growing in Rosie Steele’s beautifully planted, extensive cottage garden on the edge of the Norfolk Broads. It was entwined in an apple tree overlooking a stream where kingfishers once patrolled, before a blocking boundary fence was unexpectedly erected. Late frosts, unlikely here due to the sheltered aspect, are the principal threat to new growth – the crowns are hardy to around -15C. A fortnight earlier I had been in North Wales. Fresh snow liberally capped Snowdon and a breeze-banishing scarf and jacket were most welcome on a morning spent being shown Bleddyn and Sue Wynn-Jones’s private garden near Caernarfon in Gwynedd. I came mob-handed with disparate elements of the Joint Rock Garden Plant Committee, and such was our leisurely progress that we scarcely made it to the extensive polytunnels of the nursery proper before time ran out. The garden is an exuberant, exhilaratingly madcap, inspirational melange, in part traversed by a mountain path, which showcases a wonderful blend of plants. In the main it THE ALPINE GARDENER

ROBERT ROLFE

Holboellia latifolia in the garden of Bleddyn and Sue Wynn-Jones

underlines the extent and enterprise of the owners’ travels over many years. At one turn you chance upon a chest-high wall with Lithodora oleifolia happily, floriferously spilling grey and china blue out of every seam; at another you emerge from thick undergrowth and tunnel-like, superior shrubbery to walk beneath an extensive trellis where Holboellia latifolia has taken charge, and hangs its dark pink male flowers by the tens of thousands (the female ones are light green), flagrant and appealingly fragrant, in late April.

This belongs to the tongue-twisting family Lardizabalaceae, for long known only in Japan from aforementioned DECEMBER 2015

Akebia and a single Stauntonia representative. Yet, in 1995, Blweddyn and Dan Hinkley collected seed of Holboellia coriacea from a hedgerow near Chiba (Honshu), my excuse for the inclusion of this Himalayan to southeast Asian genus of some 20 species.

H. latifolia is considered the hardiest and the most widespread, from northeast India to China at up to 3,000m or more. The Wynn-Jones’s Nepalese introduction from 3,150m, close to the border with Tibet, will produce edible fruits in a vintage summer and is reliably long-lived, though unseasonal, bitter easterly winds will cut it down to size.

Almost always it regroups and reshoots.

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Primula sieboldii, which benefits from judicious use of irrigation

I must have been restive or inquisitive around that time, for in short succession visits were made to a couple of English rock garden/raised bed amalgamations in the east and the north of the country, both open to the public, whose advertising material in each case suggested something utterly out of the ordinary. Fully justified for one of them, overstated when it came to the other.

If (as was trumpeted on the website) the rock garden really is at its very best in early June, it’s difficult to fathom how dire it must look during the rest of the year. Non-dwarf conifers are already out 370

of scale and there are some permissible herbaceous border/transitional plants such as the elegant Veronica gentianoides and Doronicum columnae (but a miserable planting of this, clearly on its way out). There were rather desperate space fillers such scraggy delphiniums and even Russell lupins that I’d earlier seen in better order and setting on embankments as the train sped north.

As for the omissions: where to begin?

Well, perhaps with two plants mentioned earlier. Not a single Dianthus was here, yet Aberconwy Nursery’s D. ‘Eileen Lever’ is long-lived, very floriferous and THE ALPINE GARDENER

ROBERT ROLFE

Trillium grandiflorum f. roseum at Bressingham Gardens

would take many years to outgrow its space, while it is worth raising seedlings of D. ‘La Bourboule’. With me, those with the greyest leaves and the palest pink flowers have proved most effective, and they’re scented. Why on earth fail to include Hypericum olympicum, hardy as can be and resplendent in early to mid-June, when its rich yellow flowers are a joy? It self-sows gently, some of its offspring in subtler shades, and a two-tone colony looks very handsome indeed. Why not a dwarf Euphorbia? I’d certainly make space for E. myrsinites, at most 15cm in height and ideal for DECEMBER 2015

a low wall capping, the free drainage boosting its longevity, while the foliage is ornamental after the spring-produced capitulae have waned. Nor even an Erigeron, yet if you are prepared to weed determinedly, E. karvinskianus is a delicate, appealing space-filler, once admired in a coffin-sized trough at East Ruston, more recently beautifying crazy paving in a front garden only a short walk from where I live.

Best to shift my focus eastwards to the Suffolk border where, near Diss, the Blooms, father and son, have over nearly 60 years established Bressingham 371

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Anemone nemorosa, above, can be an effective partner for Primula sieboldii

Gardens. You can chug round these, transported by a narrow-gauge locomotive, or for preference walk at your leisure through dells, spellbinding narrow detours, a prefecture of signature island beds, and clever, satisfying plantings whichever way you choose to wander. On a fine day in mid-May I did just that, eventually reaching a slightly raised, one assumes leaf-mould enriched and bark-dressed bed close to (and shaded at midday by) the main house.

Woodlanders and moisture-loving plants were present in force, and I’ll make mention of another Japanese export, Primula sieboldii, which benefits from judicious use of irrigation and 372

considered positioning away from the glare of full sun. It has been grown in British gardens for just over 150 years due to the tireless efforts of Chevalier Philipp Franz von Siebold. Most of the pre-1860 Japanese introductions were thanks to him, despite his 30-year banishment from Japan after being accused of spying for Russia.

The popularity of P. sieboldii has waxed and waned, but it is nowadays bolstered by sources such as Staddon Farm Nurseries in Devon (www. pennysprimulas.co.uk), National Collection holders for the species. In the popular gardening imagination it is confined to Japan but its full distribution stretches from eastern Siberia to THE ALPINE GARDENER

ROBERT ROLFE

The Turkish Omphalodes cappadocica, another good foil for Primula sieboldii

Manchuria and Korea. In Japan societies are devoted to its cultivation, with some apparently using stages (the equivalent of auricula theatres) to exhibit potgrown specimens. It features on posters, as potted displays at railway stations and has even inspired the manufacture of sakurasoh-shaped butter cookies (sakurasoh is the Japanese name for this species).

It is remarkable how many selections are presently available: I would suggest the longstanding ‘Geisha Girl’ (light pink with a white centre and veining of similar hue), ‘Sumizomegenji ‘ (the purplish-pink petals slightly incurved and white-rimmed), ‘Inokima Minoura’ (the bright pink petals deeply lobed) DECEMBER 2015

and ‘Inukina White’ (the flattish, slender petals deeply lobed). In general, the larger the flower, the more difficult it is to blend into a planting scheme.

To divert attention from such a tour de force, distinguished and upgrading distraction is required. At Bressingham, Trillium grandiflorum f. roseum performs this function brilliantly. I’ve also seen the earlier-flowering forms offset by virginal Anemone nemorosa or brilliant blue, Turkish Omphalodes cappadocica, now available in a subtler shade of lavender, ‘Lilac Mist’. Famously the Japanese order their plantings meticulously with precision and exquisite taste. There’s no reason why the rest of us shouldn’t follow their example, after a fashion.

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Robin White, who for many years ran Blackthorn Nursery and wrote the 2006 book, Daphnes: A Practical Guide for Gardeners, shares his expertise in growing Daphne petraea, which deserves a place in any alpine collection

A flamboyant Italian to captivate every gardener

F

ew, if any, plant lovers could fail to admire and desire Daphne petraea, whether seen in cultivation or in its natural mountain habitat. This dwarf, hardy, evergreen shrub, which can cover all its foliage with fragrant pink blossom, is confined to a small area of northern Italy, west of Lake Garda, where it colonises vertical and horizontal fissures on dolomitic limestone cliffs.

Plants can be found growing in a variety of aspects. Those in shade are inevitably inclined to grow with a straggly habit, while a sunnier site encourages the tight, classic appearance. Overall, the climate in this area provides a wet summer, often in the form of heavy but local thunderstorms. An average monthly rainfall of 10cm from April to November is recorded at the northern end of Lake Garda, but the physical geography of the region influences the amount for a given area. When drought occurs, plants in sunnier spots are particularly vulnerable and it’s common to see both dead plants and specimens with dieback at these locations.

Adaptations which enable D. petraea to survive for many years in such an

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inhospitable environment are a fine, deeply searching root system; a small leaf covered with a thick, waxy cuticle to protect against water loss caused by sun and wind; and the ability to spread by stolons (underground stems) along the length of any area which has trapped a deposit of soil or organic matter.

In cultivation, the habit of mature plants falls roughly into two categories: a rounded dome or a low-growing mat.

Annual extension growth in the wild is unlikely to exceed 1.5cm, probably often less, so plants as large as 45-50cm must be of considerable age.

My original plant of ‘Grandiflora’ survived in a 9-inch clay pot in my glasshouse for more than 20 years, flowering well and providing large amounts of propagation material, largely due to allowing the root system to run into the grit dressing on the bench.

A second flush of bloom on new growth is possible during summer, particularly on young, vigorous grafted plants, but in nature only plants in the most favourable situations would produce more than a single flush, which occurs between late May and early July according to the THE ALPINE GARDENER

DAPHNE PETRAEA

A young plant of Daphne petraea showing its stoloniferous habit

season and the elevation at which plants grow. This varies from 600m to nearly 2,000m.

In the UK, plants flower between midApril and mid-May with surprisingly little difference between specimens under protection and those outside.

Growing a range of clones in the same environment shows up a difference of two to three weeks between the earliest and the latest to flower. The terminal inflorescence is formed the previous summer and is protected over winter by the narrow, persistent bracts. In the wild, poor growing conditions after flowering – typically drought – will prevent flower production for the following season.

Healthy plants start their annual vegetative growth as the flowers are DECEMBER 2015

falling. At this stage cultivated plants need some balanced feeding or pottingon and a steady moisture supply to promote plentiful blossom production for the following year. Allowing plants to become pot-bound can be fatal – the growing medium will lack the aeration essential for Daphne roots.

Commercially offered plants may be grafted on to D. longilobata, D. tangutica or D. mezereum, and will make substantial plants far more quickly than those propagated from cuttings.

However, D. longilobata is not fully hardy, so container-grown plants must not be allowed to freeze, while in the ground, the neck of the stock may be vulnerable to temperatures below –8C. Long term, I have not seen any evidence 375

PRACTICAL GARDENING to suggest that a plant on its own roots will not flower as well as grafted ones.

I suspect that all Daphne roots object to high temperatures, so containers, particularly plastic ones, should be plunged or protected from direct sun for all but the winter months. In the wild, plants will have their roots kept cool in rock fissures, but their top growth can tolerate strong sun, so containergrown specimens may well be happier plunged outside for most of the year, then protected from wet for the winter and flowering in spring.

The choice of container is not critical and neither is the compost: stick to what you have experience of managing.

For plants on their own roots, a welldrained alpine mix with a pH either side of neutral (7.0) will be fine. The roots of a stock, particularly D. longilobata and D. tangutica, may be less tolerant of dry conditions, so a higher percentage of organic matter or loam in the mix may be beneficial.

If the correct balance of site aspect and a well-drained growing medium can be achieved, D. petraea can be grown successfully without protection. A minimum of half the day in sun, more if possible, with good air circulation should be aimed for. Both these points are particularly important in the dull, damp days of winter.

Literature suggests that young plants on their own roots will grow well in tufa.

To a certain extent, I agree. However, particularly in areas of high winter rainfall, I think that tufa can hold too much moisture, which maintains a damper atmosphere around the young plants than if they were planted in a 376

crack between granite or hard limestone.

I believe that long, damp spells in winter are the main cause of leaf drop, particularly when followed by sharp frost. Some tufa-grown plants do survive well, but seldom produce much flower.

Regular liquid feeding, or drilling the planting hole right through the tufa to allow the deep, searching roots to colonise underneath or behind the rock, may solve this problem.

I have found it difficult to establish plants on their own roots in a trough or bed. This may be due partly to insufficient drainage, but the commonest problem is leaf drop in the winter. As well as debilitating the plant, dieback often follows. In early 2014, I planted some cuttings and seedlings in a sand/grit mix in a new crevice area. They all established well and have come through their first winter with no sign of problems.

I find grafted plants stand more chance of success in the open, though the lack of hardiness of D. longilobata as a rootstock may be a problem in colder areas. In the autumn of 1999, I planted a dozen or so different forms in my newly constructed ‘daphnetum’. They were planted in 15cm of 0.8-1cm Cotswold pea shingle over a slope of heavy loam – the site provided sun and good air movement but not ideal soil. In 2003, four were no longer flowering, a sure sign of trouble, and by 2005 most had succumbed in various ways, including damage from dogs feet and blackbirds! However, the two remaining clones, ‘Persebee’ and PE87/ T2, remained healthy and well budded in 2015. Whether survival is due to the genes of the clone or the rootstock is impossible to say.

THE ALPINE GARDENER

DAPHNE PETRAEA

Robin White’s ‘daphnetum’ with ten-year-old plants growing in pea shingle

For the past 30 years, the most successful way I have cultivated D. petraea is in raised beds in well-ventilated, unheated polytunnels. In some cases, the bed has only been a single railway sleeper high (22cm). For anyone who wishes to grow a number of forms purely for pleasure, constructing a bed or a frame with sides 30-40cm high, which can be covered for the winter, should be worth the effort and provide ideal conditions for other choice daphnes such as D. arbuscula and D. x hendersonii cultivars.

The top 15cm of the bed should be grit or gravel of grades 0.1-1.0cm with a more conventional alpine mix below. I DECEMBER 2015

have always planted into the top gravel without removing compost from the roots. Careful watering and feeding will be needed initially until the roots get down into the lower, more sustaining mix.

Doubtless there were numerous introductions of D. petraea throughout the 20th century, but the only named cultivar to have stood the test of time is ‘Grandiflora’ – not that surprising since it is such a wonderful form.

From the late 1980s onwards, I was fortunate enough to be given several different named selections, and in 1987, 1997 and 1999, Peter Erskine 377

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Daphne petraea ‘Cima Tombea’ puts on less than 1.5cm of annual growth

provided me with material from several populations which I grafted and grew on to evaluate.

Growing numerous forms of a single species together in identical conditions provides an opportunity to see and compare the considerable differences in their morphology. Since they were all grafted on to D. longilobata, the only variable was the individual genetics of the seed-grown rootstock which, in particular, may influence vigour of the scion. Propagated regularly over a number of years, however, it became obvious that some selections grew larger more quickly. ‘Michele’ is an example, 378

making 2.5-5cm of growth annually, while dwarfer forms such as ‘Lydora’ and ‘Cima Tombea’ manage less than 1.5cm.

Size and shape of the leaf also varies from the long, narrow, linear ‘Flamingo’ (1.7 x 0.2cm) to the short, oblanceolate ‘Lydora’ (0.7 x 0.15cm) Flower size, shape and colour all have a wide range, with flower diameter ranging from ‘Flamingo’ (1.5cm) to ‘Lydora’ (0.7cm). Shape of the perianth lobes varies from those of ‘Grandiflora’ (auriculate or broadly ovate, 0.6cm wide and overlapping) to ‘Tremalzo’ (narrowly ovate, 0.4cm wide and not overlapping).

Colour varies from white and all THE ALPINE GARDENER

DAPHNE PETRAEA

Daphne petraea ‘Flamingo’ has narrow, linear leaves and large flowers

shades of pink to a genuine red. A pale eye to the flower is not unusual, while ‘Punchinello’ has two pale inner perianth lobes and two darker outer ones. The temperatures prevailing at flowering time do seem to influence the intensity of colour from year to year, and flowers tend to fade as they age.

Propagation

Propagation is essential to help prevent indiscriminate wild collecting of this narrowly endemic species.

The forms now in cultivation should be maintained. They represent ‘the cream’ of the species, and making them DECEMBER 2015

available through enthusiastic amateurs as well as nurserymen should be the aim.

Grafting may seem too complicated for some, but cuttings are no more difficult to root than those of many alpines.

Maiden growth in semi-ripe condition (mid July) can be used, but may not be long enough to handle easily. One-yearold or even two-year-old wood will root, though it will take longer and some hormone stimulation may be necessary.

Avoid too coarse a rooting medium, which can lead to cuttings drying out.

Pure, coarse sand works well. Cuttings do not need any sophisticated treatment: I would avoid too much bottom heat, 379

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A specimen of Daphne petraea that has set seed, which can happen when more than one variety is grown together

and a cold frame or a pot in a polythene bag placed under the glasshouse bench can work as well as anything else.

I can understand a proud owner’s reluctance to chop pieces off their plant, but once a healthy plant is more than five years old, a few cuttings from around the base will not spoil the shape and may even improve air circulation to reduce the chance of fungal infection in dead foliage.

Once one has a good-sized plant of D. petraea, it is wise to propagate some youngsters as an insurance against loss of the parent. Any surplus young plants will make excellent swaps.

Seed of D. mezereum or D. tangutica is relatively easy to come by and stocks suitable for grafting can be raised in two years.

A simple wedge graft in February or March, tied with raffia or secured with pegs, can be attempted by anyone. For more information, see the chapter on 380

propagation in my book, Daphnes: A Practical Guide for Gardeners.

Growing more than one clone of D. petraea together often results in some seed production, though it is usually produced from summer flowers on new growth rather than from the main spring flush. Look out for flowers that do not fall when their remains are brown and shrivelled. A slight swelling at the base of the perianth tube will confirm seed set. Inspect regularly to avoid losing the precious seed.

If the perianth tube has split to reveal the pale greenish-yellow pericarp, the seed will detach readily and should be sown within a week or so. Germination normally occurs the following spring, though a proportion of seed that I sowed in a cold frame on September 14, 2014, germinated in late October. Seedlings should be moved as soon as the first true leaves show because there will already be a substantial root system by then.

THE ALPINE GARDENER

DAPHNE PETRAEA

The matforming Daphne petraea ‘Corna Blacca’

D. petraea ‘Cima Tombea’

Peter and Penny Watt rescued this form from a rock fall. I have grown and admired it for the last 25 years.

It is a slow-growing plant with short, broad leaves and dome-shaped habit.

Although the palest pink flowers are slightly smaller than ‘Grandiflora’, they have the same broad, overlapping perianth lobes and a distinct pale eye. I initially sold this as ‘Watts Form’.

D. petraea ‘Corna Blacca’

Introduced in 1995 by Gerard Burgonje and given to me by Harry Jans, this has a mat-forming habit and well-shaped, overlapping perianth lobes of deep pink or sometimes red.

D. petraea double-flowered form

Although it is the least attractive plant in my collection, I have grown this selection for many years. It has a DECEMBER 2015

Named forms of Daphne petraea strong constitution and a dome-shaped habit. Perhaps it is more of a botanical curiosity than anything else, as the freely produced inflorescences may fail to develop fully, and the dead blossoms do not fall.

D. petraea ‘Flamingo’

A very distinct and beautiful form introduced by Peter Erskine with the number NES99-51. Compared with all the other forms I have grown, the leaves are longer and narrower with a more acute point, and the perianth tube of 2cm is longer than any other.

The 1.5cm perianth lobes also give ‘Flamingo’ the largest flowers, which are soft pink and hardly overlap at the base. ‘Flamingo’ seems less free381

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A doubleflowered form of Daphne petraea that has a strong constitution and a domeshaped habit

flowering than some forms, and is one of the latest to flower.

old tunnel-grown plant is now 36cm x 20cm.

D. petraea ‘Garnet’

D. petraea ‘Grandiflora’

The most vigorous form, with a relatively tall but mat-forming habit. An introduction by Peter Erskine with the collection number PE97/T3 , this early flowering form does not lose its dead blossoms as easily as others, which may encourage fungal infection if grown in the open. It is irritating that in the year I gave it a clonal name the flowers were reddish pink, but most years since they have been pink. A 15-year382

A large-flowered form with a domeshaped habit, frequently eulogised in AGS journals and winner of numerous show awards since its introduction in 1914. The 1cm wide flowers are intense pink, with particularly broad, overlapping perianth lobes.

D. petraea ‘Idro’

A selection by German plantsman Hans Bauer, presumably from the region THE ALPINE GARDENER

DAPHNE PETRAEA

Robin White’s 15-year-old specimen of the vigorous Daphne petraea ‘Garnet’

round Lago d’Idro, with reddish-pink flowers and a low, mat-forming habit.

D. petraea ‘Lydora’

Perhaps Peter Erskine’s best introduction, with the number PE97/T13, named after his two granddaughters, Lydia and Flora. It is slow-growing and forms a perfect dome.

The inflorescences have five to seven small flowers, but are produced in such profusion that most of the foliage is hidden when a specimen is well grown.

The colour is a genuine crimson with a paler eye.

D. petraea ‘Michele’

One of the most vigorous forms. This was a low-level selection (600m) from the west side of Lake Garda, made by Margaret and Henry Taylor in the early 1990s. The habit is dome-shaped and DECEMBER 2015

the flowers are mid to pale pink. Strong young plants often have axillary as well as terminal inflorescences. ‘Michele’ also produces more summer blossom on maiden growth than most forms.

D. petraea ‘Persebee’

A selection with the number PE97/ T14, also named after Peter’s granddaughters, Persephone and Beatrice. It is vigorous with a dome-shaped habit. Strong growth produces axillary as well as terminal inflorescences. The flowers are deep pink, sometimes red. A grafted example planted in my ‘daphnetum’ in 1999 still remains healthy, measuring 25cm wide x 15cm high.

D. petraea ‘Punchinello’

A selection with the number PE97/ CB1. It is distinct in having flowers with 383

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The two-tone flowers of Daphne petraea ‘Punchinello’ and, right, D. p. ‘Persebee’ the two inner lobes palest pink, the two outer ones deeper pink. This contrast is most noticeable in flowers produced during the main spring flush. Domeshaped and relatively slow-growing.

D. petraea ‘The Beacon’

I sold this selection by Peter Erskine under the number PE87/C for some years before deciding it was distinct enough to deserve a cultivar name. It is the earliest plant to flower, and the absence of hairs on the perianth tube gives the flowers a particularly intense shade of pink. It has a low, mat-forming habit.

D. petraea ‘Tremalzo’

I believe this is the only white-flowered form ever found. It was introduced by Ernst Hauser in the mid-1970s and named after the area where it grew.

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Even grafted plants are comparatively slow-growing, eventually making a dome shape. The leaves are relatively short and broad, and often paler green than pink-flowered forms. The flowers remain pure white throughout their life, with a wonderful crystalline texture shown to perfection in sunshine.

D. petraea ‘Tuflungo’

A selection made in July 1991 by Robert Rolfe, who noticed that while most plants on Cima Tuflungo had finished flowering, this plant was in full bloom. This late-flowering habit persisted in cultivation – mid-May in the East Midlands. The flowers, which are produced on a low-growing, mat-forming plant, are strong pink in colour. A plant grafted on D. tangutica won the Farrer Medal at an AGS show in 1999.

THE ALPINE GARDENER

DAPHNE PETRAEA

Daphne petraea ‘Vanguard’ and, right, the unique white-flowered D. p. ‘Tremalzo’

D. petraea ‘Vanguard’

I raised this selection from a seed produced by ‘Cima Tombea’. The compact habit and well-shaped flowers with broad perianth lobes and pale eye come from the seed parent, while the early blooming and strong pink colour suggest the pollen came from ‘The Beacon’, which was growing nearby.

Some numbered forms worth a mention:

D. petraea CDB11554

I lost my stock of this some years ago.

It had a very low, spreading habit and was late-flowering. The blooms had a long, pale pink perianth lobe.

D. petraea PE87/F

Quite a few plants of this selection have been sold and specimens here DECEMBER 2015

continue to grow vigorously to make a tall mat rather than a dome. The flowers are bright pink.

D. petraea PE97/T2

This was one of the 1997 selections which I planted in the ‘daphnetum’ in October 1999. In 2015 it continues to thrive, measuring 30cm wide x 18cm high. The flowers are mid-pink.

This plant seems to have a good constitution.

I am grateful to Peter Erskine for providing details of the habitat of Daphne petraea. Reference: The Smaller Daphnes, ‘Daphne petraea: A Review’, by Peter Erskine, published by the Royal Horticultural Society in association with the Alpine Garden Society, 2001.

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I

have been gardening on light sandy soils for over 45 years. In principle, one might think that these would be ideal for the growing of alpines: good drainage and low nutrient levels which will ensure slow, tough growth and floriferousness. In practice, things are never as simple as that. When were they ever?

These soils dry out very quickly, so if a dry summer arrives before alpines planted in the spring have put down deep roots, they die. The most expensive plants, of course, die most quickly.

Autumn planting becomes the norm.

Consult any basic gardening book and the solution is clearly set out: dig in copious amounts of garden compost or other bulky organic material, and your soil will be miraculously transformed into the soil of your dreams, which will grow primulas or pulsatillas, cabbages or carrots with equal ease.

Strange as it may seem, this is exactly the same recipe as that given for the improvement of heavy clay soils, except in this case grit and lime may be added.

But I have been told by some people who have heavy clay that they have been following the recommendation for 30 or 40 years, and now doubt if they will live to see this promised transformation take place.

From the gardener’s point of view, the ideal soil should contain a suitable balance of three main ingredients: sand to provide good drainage; clay to absorb nutrients and hold on to them, then release them as nutrient levels in the soil moisture fall; and humus (partly decayed organic material) to produce an

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Succeeding with choice shrubs in sandy soils Whether it’s a Rhododendron, Daphne, Pieris or Kalmia, Vic Aspland has experienced triumphs – and disappointments – growing shrubs in ‘beach-like’ soil

open, spongy texture which will let air into the soil, prevent compaction, retain moisture and gradually supply nutrients as further decomposition takes place.

Oh! How few of us seem to have this ideal.

But let’s return to my sandy soil.

In our first garden, we followed the recommendations, digging in all the compost we could make. It did no good.

Over the years we learned that these soils are ferociously ‘hungry’. No matter how much compost we added, it all disappeared as if by magic. Indeed, after 29 years of this, we still had a border which I could not dig with a garden fork – it was like running the fork through THE ALPINE GARDENER

SHRUBS FOR SANDY SOILS

Rhododendron hirsutum ‘Flore Pleno’ – the hairy Rhododendron without hairs!

a beach! I chose the word ‘ferociously’ with good cause.

I erected a new fence at the bottom of the garden, using larch posts pressuretreated with wood preservative – the sort that you expect to last a lifetime, or at least half a lifetime. Within 18 months, the fence began to show signs of instability. Investigation revealed that exactly at soil level, the four-inch thick posts had been reduced to the thickness of my little finger. Two inches below the soil surface, the posts were ‘as new’.

It would appear that given access to sufficient oxygen at the surface, and in the absence of anything else to consume, the soil organisms eat the wood and DECEMBER 2015

the preservative too. Repairs involved bolting the above-ground posts onto concrete godfathers, which proved to be too much for the varmints to digest.

This provided an object lesson: any organic material within two inches of the soil surface would be rapidly consumed. I adopted an alternative nodig strategy.

The only time I dug the garden was when I put in a new plant. From here on, all organic material was placed on top as a mulch. The aim was to keep the soil cooler and to prevent the evaporation of moisture from the surface. In addition, as it decomposed, it provided a steady downward flow of nutrients to the plant 387

PRACTICAL GARDENING roots. Where I wished to grow screetype plants from the Mediterranean area, a gravel mulch was placed on the surface, and the soil left unimproved.

So much for the trials and tribulations of sandy soils, but what of the benefits?

Perhaps the most significant is the fact that the pH is often neutral (samples around my present garden give readings of 6.9 and 7.0). This means that almost any type of plant can be grown.

You don’t have to worry about whether a plant is intolerant of lime, so you can grow Ericaceae, and there are very few alpines which actually need lime, so you can grow most other things too. Provide enough water and, in some cases, shade and you can grow almost anything.

But what of the plants? The ones I will mention have all shown considerable drought tolerance and have performed consistently well. I will begin with Ericaceae.

Rhododendron impeditum ‘Pygmaeum’ is a gem. The leaves are tiny, grey and covered with small scales (tip: small, scaly leaves usually mean drought tolerance). After 40 years or so, it has made a compact mound only 1½ft high and 2½ft wide (from here on I will give sizes as height x width). Each year the foliage almost disappears under a blanket of bluish-purple flowers. I have little doubt that in richer soils the growth rate would be faster.

R. racemosum ‘White Lace’ has larger leaves and a more upright habit. After 20 years or so, it has still only reached 2½ft x 3ft, though it was planted in a very dry area close to a Cupressus macrocarpa hedge. Since I have removed the hedge, the growth rate has increased. When it 388

is in flower, the epithet which readily springs to mind is ‘charming’. The flowers are small, funnel-shaped and white, with many protruding white anthers.

Perhaps the star turn in our present garden is R. hirsutum ‘Flore Pleno’. It is an oddball. As seen in the wild, the leaves of this species are ciliate: they have hairs like eyelashes along the edges. Hence hirsutum: hairy. And here is the oddness – this double-flowered form has leaves which are not ciliate. So, I have the hairy Rhododendron without hairs. I bought it from Glendoick Gardens in October 1982 and it was moved to our present garden. Is it a dwarf? Well, it has grown steadily, in spite of the unimproved soil, and has now reached 2½ft x 6ft – perhaps a little too big, but it does give all-year value. I will begin a course of gentle pruning next year.

The clusters of flowers are an attractive deep pink verging on red. The leaves are slightly scaly and, when the sun is bright in summer and especially if it runs dry at the root, the older leaves take on an attractive autumnal red tinge which is confined to the edges of the younger ones. Nature itself has provided me with an additional attraction. When I first planted the Rhododendron, there was a straggly Lithodora diffusa in the bed behind it, and it has gradually extended to grow right over the latter.

No problem. The Lithodora now climbs up through it and flowers freely, long before the Rhododendron flowers appear and then sporadically at other times, so I have alternately blue then red then blue flowers and leaf interest too, all from the one patch of ground. I would not want to be without R. dauricum, which begins THE ALPINE GARDENER

SHRUBS FOR SANDY SOILS

Rhododendron hirsutum ‘Flore Pleno’ displaying its unusual and attractive autumnal tinges. Right, Lithodora diffusa growing through it in spring

to flower in January and offers its pinkflowered display for about a month. It is largely deciduous and, again, has small leaves, signalling drought tolerance.

In the 1960s and 70s there was a great fashion for plantings of smaller conifers and heathers, and Adrian Bloom did much to popularise this with a number of beautifully illustrated books. Although nurseries still feature heathers, I do not see examples of this kind of gardening any more. In my own garden I have only one example of the group: Daboecia cantabrica (St. Daboec’s heath). It is said to be lime-intolerant, so is quite safe with me. I grow it because DECEMBER 2015

the flowers are much larger than those of the other heathers and heaths and a good, deep, glowing red-purple (it is difficult to describe the colour). When pollinated, the individual flowers fall off while still coloured, so it stays looking tidy rather than holding on to a spike of tatty dead flowers, like its relatives.

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Rhododendron dauricum begins to flower in January, its display lasting for about a month

Flowering begins in late spring and there are still flowers present as I write in early November. It also has geographical interest, being native to south-west Ireland and northern Spain. It is said that it was pushed to these fringes of Europe during the last Ice Age, and remained there when the ice receded.

Menziesia ciliicalyx was added to my 390

collection because it was ‘something different’. The tubular soft-pink flowers are quite large. It was planted in a westfacing border which has quite a lot of shade and it has grown well enough, but has produced a rather unsatisfactorily straggly plant. I am debating whether to move it to a sunnier position or severely prune it (or both). There are THE ALPINE GARDENER

SHRUBS FOR SANDY SOILS

Daboecia cantabrica can flower from spring until late autumn

more compact forms available, which occasionally make an appearance at AGS shows. It gives a fine display of autumn colour, the leaves gradually changing, in patches rather than all over, from pale green through yellow, orange and red, and some red patches deepen to almost black. All colours are present at the same time.

Another ‘something different’ was the strawberry tree. We had seen Arbutus unedo during many of our holidays in Greece and the Greek islands, and fancied having one to remind us of our trips. As it transpired at the time we could find only A. x intermedia. It did well, the sprays of off-white flowers DECEMBER 2015

being followed by round red fruits. In the wild, we have found that these really do taste like strawberries but only when they are very ripe.

We had two problems with this plant.

First, each year the blackbirds would decide that the fruits were edible before we did, so we never got to eat any.

Second, it grew and grew. Progress was slow at first: it took six years to reach a height of four feet or so and the attractively rough, shaggy bark began to make an impression. Then it got into second gear and began to accelerate.

The next year it was up to six feet and I began light pruning. And then it was racing past eight feet despite pruning.

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PRACTICAL GARDENING With regret, we decided that it had to go. An AGS member living less than a mile away had the same problem with A. unedo. Moral: if you have a small garden, Arbutus are not for you.

Kalmia latifolia has leaves quite similar to those of the Arbutus, but is much better-behaved. I am surprised that they are not more widely available due to the fact that these denizens of eastern North America have been in cultivation in Britain since 1734.

The shape of the flowers is unique.

The buds are reminiscent of little dabs of icing sugar applied from a piping bag and are an appropriate shade of pink or red. When the flowers open they take the form of ribbed bowls, not unlike opened umbrellas. My first acquisition, ‘Alpine Gem’, came from Glendoick Gardens in November 1999, and has still only reached 3ft x 2½ft. Its location has now become too shaded by other things, so it doesn’t flower as freely as it used to, so I will probably have to relocate it in the spring.

When selecting a new position, I will be more careful in my choice than I was when I moved my second cultivar, ‘Ostbo Red’, obtained from Ashwood Nurseries in June 2000. It had reached 2½ft x 3ft and needed to be moved to a sunnier place for the same reason. Have you noticed this phenomenon in your own garden: when you need to move a plant, or plant an impulse purchase, you find that there is only a single place available (unless you are prepared to dig up and shuffle half a dozen plants at the same time)? So it was with ‘Ostbo Red’. The first season after the move the display of flowers improved greatly.

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Success! But then the older leaves began to yellow and it took on a sorry appearance, made worse by the fact that the yellow leaves were not shed, but hung on like a reproach. Drought?

No. Despite spot watering, new leaves developed but more old ones yellowed.

And then the penny dropped.

Three feet away was a cluster of limestone blocks around the base of a venerable old specimen of Rosmarinus officinalis. (Accompanied by Arum creticum, this is a reminder of happy times spent in Crete.) I have never before seen any ericaceous plant so profoundly affected by even the proximity of limestone. Drastic conditions need drastic remedies, so I moved it again in June, just about the most unsuitable time, to a newly cleared, west-facing border.

Ericaceae in general are easy plants to move because most of them form a dense, rather shallow mat of roots, though there may be a thick, anchoring tap-root down below. If you insert a spade vertically into the ground around the edge of the leaf canopy first, then gradually work down to a more horizontal position, the root mat can be gradually raised and any anchoring roots severed without major damage.

Relocation was followed by a heavy mulch of compost and regular watering.

The patient is now recovering (no more yellow leaves) but has a rather leggy look due to the removal of the yellowed ones, which did not revive, so a little judicious pruning will be needed to make it more compact. Next year, when I move ‘Alpine Gem’, similar tactics will have to be employed.

THE ALPINE GARDENER

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Kalmia latifolia ‘Ostbo red’, one of several desirable cultivars in this genus

Judicious pruning would seem to be a recurring theme in my plans for next year. Many plants reach a stage at which they are a little too tall, a little too wide, a little too straggly and so on. Regular light pruning in good time is a far better choice than heavy and infrequent bouts.

(I must remember that.)

Another advantage of Ericaceae is that most of them respond well to pruning.

As an extreme example, many years ago a very large specimen of Pieris formosa var. forrestii ‘Wakehurst’ in the garden of Jim Broadhurst, at the time secretary of the Birmingham AGS Group, was DECEMBER 2015

apparently killed during a severe winter.

With sorrow, it was sawn off at ground level ‘to tidy up’ and removal of the roots was pencilled in for some unspecified later date. Delaying this job proved to be fortuitous. By June, new shoots began to appear from the old stump, just below ground level, and it regenerated completely. I would not recommend this level of severe pruning to anyone, but it does show what is possible.

Over 20 years or so in our previous garden, Pieris ‘Forest Flame’ built up to a fine plant perhaps six or seven feet tall.

The new spring foliage is a vibrant red, 393

PRACTICAL GARDENING fading gradually – like autumn in reverse – through orange, pale yellow, cream and pale green to a moderately dark green. Add in the abundant panicles of white urn-shaped flowers and you have amazing value in one plant.

This is one of those plants that always seemed to be around and I had assumed that it had a long history in cultivation, but now I find that it is a hybrid between P. formosa forrestii ‘Wakehurst’ and P. japonica, and was raised and introduced

by Sunningdale Nurseries about 1957.

We did not move it to the new garden because we were pleased to find a small specimen already in place. As things turned out, this proved to be a mistake: it grew poorly and slowly. After 17 years it had still only reached a spindly four feet in height. Then, mercifully, during the last winter it died! There was no apparent reason: the leaves fell off and then it was dead.

I am just too soft-hearted with plants and can’t bring myself to get rid of them.

Each spring I thought that it would ‘come on well this year’, but now I don’t have to make up my mind. Perhaps the replacement will go into a slightly different position. Pieris japonica ‘Ralto’ slipped through the net of my plant records system. I have no idea whether I bought it or whether it was present in the garden when we came here. Last spring I ‘rediscovered’ it in a position much overgrown by coarser subjects where it had languished for years. With this tough competition it was in poor shape and less than a foot tall after the dead and/or straggly stems had been pruned off. After its first season in a better location it is regrowing nicely to 394

form a compact shrub. The leaves are discreetly variegated with cream around the edges.

Variegated plants can be overdone, and I know some AGS purists who hate them, but some can add an extra dimension to the garden. Daphne x burkwoodii ‘G. K. Argles’ I would also describe as discreetly variegated. The rather narrow leaves bear a variable margin of creamy gold. I am rather pleased to have propagated this myself by grafting a cutting onto a seedling understock of D. mezereum. After 15 years it has reached 3½ft x 4ft but has a very open structure so casts little shade. This means that I can underplant with Cyclamen coum for winter flower. Add pink buds opening to scented white flowers and what more could one ask?

Very similar in appearance at first glance is D. x transatlantica ‘Beulah Cross’. This is a hybrid between D. caucasica and D. cneorum of gardens, first raised in the USA. I positioned ‘G. K.’ and ‘Beulah’ on either side of a stepping-stone path cutting across a bed. I was interested to compare and contrast the two. The latter was rather slower growing but produced a similarly rounded bush and was as floriferous until, on reaching about a foot tall, it rapidly died! I don’t know why.

A far better version of this cross is Robin White’s ‘Eternal Fragrance’, which to my mind is the garden Daphne. It is robust, floriferous and repeat-flowering.

I made a serious mistake with one specimen. I had thought that it would make a nice exhibit for the show bench, so potted it up in a 30cm half-pot. This was placed in a plunge bed filled with THE ALPINE GARDENER

SHRUBS FOR SANDY SOILS

Daphne x burkwoodii ‘G. K. Argles’ has discreetly variegated leaves

composted bark, outside in full sun to encourage compact growth. But then I had other issues to cope with for a while.

When I next looked at it, it was edging towards 2ft x 3ft. Clearly it had rooted into the plunge bark and found this very nutritious. Now I am faced with a problem. I will have to remove it from the plunge next year and prune it back to a more moderate size. Will it survive the root disturbance? Who knows? I am more optimistic about the pruning aspect though.

Daphnes have an undeserved reputation for being difficult but, if you pick the right ones for your conditions, they can be very long-lived. In a recently DECEMBER 2015

cleared area I have planted two seedlings of the form of D. mezereum which has deep red flowers and correspondingly dark berries. Based on my past experience, I can expect these to last my lifetime. Not bad for £4 each.

By now you may be getting the impression that my garden is full of nothing but choice Ericaceae and daphnes. Far from it (although in my mind, all the plants I have chosen to plant are ‘choice’). It holds an eclectic mix of alpines, shrubs, small trees, bulbs and others. Bulbs which have flourished in my sandy soils will be the subject of a future article.

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Floral treasures of the Mediterranean islands

I

slands, because of their isolation from other areas, are usually a source of plants that are not found elsewhere, and this is certainly true of the Mediterranean islands.

Certain genera, such as Paeonia, Ophrys and Crocus, are prone to develop local endemics, so islands such as the Balearics, Crete and Rhodes have their own peony species (P. cambessedessii, P. clusii and P. rhodia respectively).

Depending on whether you are a ‘lumper’ or a ‘splitter’, most islands have their own Ophrys species, particularly the larger islands such as Sicily, Crete, Cyprus and the eastern Aegean islands.

Endemic Crocus species are present in the Balearics, Corsica, Cyprus and Crete.

Other bulbous genera such as Tulipa, Fritillaria and Colchicum have individual species which are restricted to the islands. The genus Pancratium is an interesting example where P. maritimum occurs in coastal situations all round the Mediterranean, but the mountain equivalent, P. illyricum, is found mainly in Corsica and Sardinia.

Some island species, such as Lathyrus odoratus from Sicily, are one of the parents of common garden plants, in this case fragrant sweet peas.

Ranunculus asiaticus from the eastern Mediterranean is equally the parent of the double-flowered Ranunculus planted

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The Alpine Garden Society’s slide library contains more than 40,000 images, the majority of which have never been published.

In this feature, which has become a regular part of our December issue, slide librarians Peter Sheasby and Ann Thomas choose a selection of photographs on a specific theme. This year they have opted for plants from Mediterranean islands. As well as showcasing photographs from the slide library, this feature brightens the bleak days of winter and whets the appetite for all the wonderful sights that we hope to see in wild places during 2016.

as short-lived perennials. In contrast we regularly grow the wild species such as Tulipa bakeri from Crete, Iris unguicularis from many areas, Narcissus tazetta and N. poeticus, Sternbergia sicula and Ornithogalum nutans.

Morisia monanthos from Corsica and Sardinia is a popular alpine.

Bulbs of the Eastern Mediterranean by Oron Peri, just published by the Alpine Garden Society, includes detailed coverage of the bulbous, tuberous and rhizomatous plants of Cyprus.

Peter Sheasby THE ALPINE GARDENER

MEDITERRANEAN ISLANDS

Crocus corsicus on the Col de Vergio, Corsica (Peter Sheasby) Below, Tulipa saxatilis at Omalos, Crete (Peter Sheasby)

DECEMBER 2015

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Serapias neglecta near Ajaccio, Corsica (Peter Sheasby)

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THE ALPINE GARDENER

MEDITERRANEAN ISLANDS

Cushions of Euphorbia acanthothamnos near Chora Sfakion, Crete (Peter Sheasby) Below, Glebionis coronaria en masse in northern Cyprus (Peter Sheasby)

DECEMBER 2015

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Left, Simethis mattiazzii near Bonifacio, Corsica (Peter Sheasby) Right, Ophrys speculum subsp. regis-ferdinandii on Rhodes (Peter Sheasby) 400

THE ALPINE GARDENER

MEDITERRANEAN ISLANDS

Anemone hortensis near Siracusa, Sicily (Peter Sheasby) Below, the parasitic Cytinus ruber on Sardinia (Peter Sheasby)

DECEMBER 2015

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Convolvulus tricolor at Baucina, northern Sicily (Percy Small) Below, Ranunculus asiaticus on Cyprus (Jim Archibald)

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THE ALPINE GARDENER

MEDITERRANEAN ISLANDS

Gladiolus triphyllus near Episkopi, Cyprus (Peter Sheasby)

DECEMBER 2015

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The striking Arum idaeum near Ideo Andro, Crete. It is endemic to the island (Peter Sheasby)

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THE ALPINE GARDENER

MEDITERRANEAN ISLANDS

Morisia monanthos on Sardinia (Peter Sheasby) Below, Tulipa agenensis on the Greek island of Chios (Peter Sheasby)

DECEMBER 2015

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The parasitic Cynomorium coccineum near Cagliari, Sardinia (Peter Sheasby)

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THE ALPINE GARDENER

Clockwise from above left: Lathyrus odoratus near Cefalù, Sicily; Ophrys kotschyi near Kyrenia, Cyprus; Crocus sieberi subsp. sieberi on the Mount Ida plateau, Crete; Ophrys lacaitae near Siracusa, Sicily (all Peter Sheasby)

DECEMBER 2015

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Kings and queens of the cabbage patch

A mauve-blue form of Heliophila juncea puts on a spectacular show on the Skurweberg in South Africa’s Western Cape, with the orange annual Arctotis fastuosa.

Photograph by Colin Paterson-Jones

In this wide-ranging feature, Robert Rolfe assesses the present-day position of alpine brassicas in cultivation. On page 444, Martin and Anna-Liisa Sheader select choice South American outliers

BEAUTIFUL BRASSICAS

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CHRISTOPHER GREY-WILSON

‘R

evenge is sweet – or savoury,’ declared Rannveig Wallis, serving up a salad made enticingly peppery by the addition of hairy bittercress (Cardamine hirsuta) at the AGS South Wales Show judges’ lunch in February 2013. This, surely the most pestilential of all the hundreds of crucifers introduced (in this case inadvertently) to gardens, flings its seeds far and wide, where they germinate by the thousand. Weed out every scrap and beware: the least fragment remaining will take hold.

This banish-on-sight edict applies to some other members of Brassicaceae (Cruciferae of old), for the family harbours a sizeable flock of black sheep.

Yet even Cardamine, while including a few of these, provides horticulturists with welcome species such as C. macrophylla, AGM-rated C. pentaphylla, and C. pratensis or lady’s smock, which has various cultivars, ‘Flore Pleno’ the most widely grown.

One could say the same of Draba, Lepidium and a dozen others. Unlike Primulaceae (in which genera such as Dionysia, Primula, Omphalogramma and Soldanella have a very high proportion of ornamental species), with Brassicaceae it is wise to pick and choose rather carefully. As Paul Furse wrote after his 1962-63 trip to Iran and Turkey, members of the family ‘were innumerable and grew everywhere, as weeds of cultivation, as fodder and as beautiful rock plants’.

This proviso aside, there are many distinguished representatives that uphold the reputation of the family as

The clambering Aurinia saxatilis

an important element of spring and summer garden displays, and certainly as a mainstay on the dinner plate. There’s even a Brassica Growers Association, admittedly of an agricultural rather than a horticultural persuasion, its spokesman last year invoking my favourite latterday adjective, ‘Goldilocksian’, to celebrate optimum conditions throughout the British Isles last autumn for Brussels sprouts: ‘Not too hot or cold, and not too wet or dry.’ It was a promising year, too, for the sprout/kale hybrid, launched in the United States as ‘kalette’, a modish superfood.

Setting aside all the edible options, from THE ALPINE GARDENER

CHRISTOPHER GREY-WILSON

BEAUTIFUL BRASSICAS

Arabis caucasica growing happily with several colour forms of Aubrieta

radishes and watercress to cabbages, cauliflower and broccoli, and farmers’ crops such as mustard and oilseed rape, who has not grown wallflowers, highly scented stocks, Honesty, or ‘rockery’ favourites Iberis sempervirens, Aurinia saxatilis and various cultivars of Aubrieta? If you will excuse the pun, these are all stock-in-trade occupants of many gardens, for all that their rarefied, often distinguished relatives grace far fewer. I know of a cragside garden in Derbyshire where Arabis caucasica has naturalised to spectacular effect: our picture shows it in happy association with several colour forms of Aubrieta.

DECEMBER 2015

Aurinia saxatilis comes just a few days to a week later, but manages to chime with all of the foregoing, though it is very satisfactory indeed planted by itself, atop, in the crevices of and at the base of stone walls.

These obliging plants thrive in a variety of soils – even in the multi-purpose composts that are seldom suitable for the long-term cultivation of alpines – but are best in a rubbly, well-drained, alkaline mix.

The best part of 60 years ago, Roy Elliott put together an overview, ‘In praise of Crucifers’ (AGS Bulletin 1958, volume 26, pages 262-7) declaring 411

BEAUTIFUL BRASSICAS ROBERT ROLFE

Alyssum (Ptilotrichum) pyrenaicum sets an abundance of viable seed

his great fondness for them. It was intended to counter Reginald Farrer’s broad-brush dismissal of the family.

Since then a great deal of taxonomic work has been carried out, numerous names have been coined, supplanted, or else reconfigured, and horticulturally significant introductions have been made in each ensuing decade. Present on every continent bar Antarctica, and encompassing well over 300 genera, Brassicaceae includes numerous bona fide alpines, some reaching dizzying altitudes of up to 5,000m, exceptionally to 6,400m in the case of the Tibetan Lepidostemon everestianus.

What follows concentrates on alpine representatives of this family the world over. I’ve endeavoured to 412

steer a course between the familiar and the undeservedly obscure or underused in gardens. A scattering haven’t been mentioned, never mind illustrated, in this journal before.

The alpine members of the family range from the perilously rare to the ubiquitous.

In the first camp, the Croatian Degenia velebitica has a distribution limited to an area of under five hectares, with an estimated 37,000 individuals, at 1,2001,300m, centred on Velika Kapela. This, despite the discovery of a further locality in the late 1990s. A reduction in grazing has caused a detrimental increase of grasses, sedges and Arctostaphylos uvaursa, but a conservation programme has been instigated and early results are encouraging. Apparently no longer THE ALPINE GARDENER

JIM ARCHIBALD

BEAUTIFUL BRASSICAS

Crambe orientalis, from Turkey and Iran, makes an excellent garden plant

found at its locus classicus, Plana, it is assumed to have succumbed there to the rampant spread of gorse. On the other hand it has settled down very well in cultivation, where the attractive greyishsilver mats are sometimes smothered with clear yellow flowers of generous size, followed by seed pods akin to Honesty in miniature, whose contents are best sown fresh or even while still green.

Limestone cliff-dwelling Alyssum (Ptilotrichum) pyrenaicum, from a single site in the French Pyrenees, was represented by around 1,000 plants at the last count, yet in gardens sets an abundance of viable seed. And the Greek Aubrieta glabrescens, restricted to the summit of Smolikas, has also settled down well in cultivation. Contrast DECEMBER 2015

these three narrow endemics with the ubiquitous Arabis alpina, spread across the northern hemisphere from northeastern USA to Lapland, over to western Siberia and as far south as the mountains of Ethiopia, Kenya and Tanzania.

The family has its main strongholds north of the Equator, with Turkey through to Central Asia, Mediterranean and north-western USA of particular note. However, the Andes also have significant representations, while southern Africa and New Zealand are home to noteworthy outliers. Only three genera ‒ Cardamine, Lepidium and Rorippa ‒ are represented throughout, but others, such as Draba, are very widely spread, while other non-indigenous genera have made themselves at 413

BEAUTIFUL BRASSICAS ROBERT ROLFE

Malcolmia maritima punctuated by Anemone coronaria at Cape Sounion, Greece

home abroad. Hence the presence of Alyssum minutum in southern Africa, and the Eurasian wild turnip (Brassica tournefortii) in Australia and parts of western USA – an invasive and most unwelcome addition to their floras.

There’s only space here to concentrate on a tithe of the ornamental or unusual alpine Brassicaceae: Aethionema, Erysimum, Thlaspi and Hesperis are among those that regrettably receive the barest of mentions, yet each deserves the attention of the discriminating gardener.

Representatives fit every conceivable niche in the garden, and come in a progression of statures, from minuscule to strapping. Bridging the gap between the vegetable and the ornamental garden, Crambe maritima, long ago 414

recommended by Gertrude Jekyll, was used to great effect in the idiosyncratic Dungeness garden of film director Derek Jarman and brought to wider attention after it was chanced upon by Beth Chatto and Christopher Lloyd. But the scale of this kale is eclipsed by Caucasian C. cordifolia, which erupts in summer to a height of almost 2m high and wide, the small, scented white flowers arrayed in their thousands. Iranian/Turkish C. orientalis, just over half this height, is also well worth growing.

Attaining the same height, yellow (but either white or green in certain other species) Stanleya pinnata is the most widespread of seven western/ south-western USA representatives, subshrubby in this example and THE ALPINE GARDENER

ROBERT ROLFE

BEAUTIFUL BRASSICAS

Pritzelago (Hutchinsia) alpina illuminates a grey crag in the Swiss Alps

distributed at up to 1,800m, from Oregon and California south to Arizona and Texas. The inflorescences have repeatedly been compared with those of Asphodelaceaeous, Asian Eremurus, and from a distance look nothing like those of a legitimate Brassicaceae member.

Despite a reputation for intransigence in cultivation, it was for long grown in a warm, dryish border at RBG Kew and has been offered by a few British nurserymen. Requiring a fiercely drained and sunny spot, it resents crowding, other than with its own sort.

Good companions

Having said this, crucifers of all persuasions also make excellent companion as much as statement plants, DECEMBER 2015

both in the wild and in gardens. In southern Greece, early one March, I admired Malcolmia maritima (Virginia stock) on Cape Sounion, forming drifts in which scarlet red Anemone coronaria proliferated to audacious effect. Later the same year, in Switzerland, I encountered a white-on-white association involving Pritzelago (Hutchinsia) alpina and Ranunculus alpestris, both growing in their tens of thousands in crags and on moraine below the Eiger, not far from the penultimate cable car station. At much the same altitude (2,543m), but in north-western Turkey this time, and having trudged all the way to the top of Ulu Dağ, on the summit slope I was treated to the dazzling combination of clear blue Veronica caespitosa and rich 415

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yellow Draba bruniifolia, colonising the equally dazzling white limestone almost to the very top. Comparably vivid tableaux are repeated worldwide, suggesting that family members have a happy knack of choosing the best of neighbours.

Taking just one further example, in a very informative article for the Bulletin of the American Rock Garden Society in 1990 (‘Physarias: April’s Garden Gold’, volume 48, pages 111-20), Panayoti Kelaidis conjured up images of members of the genus Physaria ‘decorating screes and roadsides by the acre’ in parts of the Rocky Mountains and Intermountain West, with one of the most attractive species, yellow or orange P. alpina, extensively mixed with deep purple Oxytropis podocarpa in one Colorado locality and with Eritrichium nanum in another. ‘Either combination,’ he observed, ‘would be the envy of any gardener.’

In a non-alpine context, an enduring gardening tradition involves interplanting wallflowers and lateflowering tulips. Decidedly formal, it presages another long-established horticultural trick using crucifers ‒ an edging of bright blue Lobelia erinus interspersed with Lobularia maritima (sweet Alison or Little Dorrit). Not to all tastes: not to mine. It’s a painting by numbers exercise, discordant even at the fringes of the rock garden, unthinkable within. Here, or in troughs, a less schematic planting is desirable, for all that it might take a calculated degree of planning. Balancing growth synchronicity, repeat plantings, time of flowering and colour harmony all play

their parts.

In containers, my most successful juxtapositions have involved pink, Balkan Thlaspi bellidifolium (the most obliging of its genus and long-lived) with a glossy white Saxifraga diapensioides hybrid, or else, diametrically opposed, the elegant, restrained Aubrieta deltoidea ‘Nana Variegata’ surrounded by silver saxifrages, Sempervivum arachnoideum, Edraianthus pumilio and the elegant, silvery-white foliage of the Greek Achillea umbellata (a Mount Dirfi introduction). These have endured five or more years, with judicious pruning once or twice per annum restraining the THE ALPINE GARDENER

ROBERT ROLFE

BEAUTIFUL BRASSICAS

Pachyphragma macrophyllum brightens shady and damp areas in March Left, Arabis procurrens ‘Aureovariegata’ with Anthemis marschalliana

more vigorous plants.

Opportunities abound on the rock garden proper, though it be should said straightaway that I eschew the doubleflowered forms of Arabis and Alyssum that have been bred. Nor do I find that the variegated sports marry well with their neighbours, with the exception of Arabis procurrens ‘Aureovariegata’, an excellent foil when yoked with silvery Anthemis marschalliana (A. rudolphiana in some old catalogues, and with a slightly unruly display of bright yellow flowers, arguably best lopped off to enhance the foliage effect).

Otherwise, overall it’s best to focus on DECEMBER 2015

a mid to late-spring display, but with heralds as early as mid-March. The pink, Cypriot Arabis purpurea is very effective if planted close to Saxifraga oppositifolia; white Aethionema iberideum is another at its best early in the year, which I once contrived to have spilling over a rock ledge, with Crocus tommasinianus behind.

For damper, shadier positions, Pachyphragma macrophyllum blooms straight after the snowdrops and winter aconites finish, its new leaves light green against their rather fleshy, blackish older remnants. For whitening a ditch, a shady defile or, more extensively, a damp 417

BEAUTIFUL BRASSICAS ROBERT ROLFE

Alyssum purpureum in the Sierra Nevada, Spain

copse, it’s invaluable.

Scores of similarly congenial partnerships are worth considering or creating. I’ll curtail this section by recommending Alyssum (Ptilotrichum) spinosum in either its white or pinkflowered forms ‒ it’s long-lived (benefitting from a shearing over after flowering), drought-tolerant, quietly attractive in greyish leaf, easily grown in any well-drained spot and usefully continues the rock garden display throughout late May and into the first days of June. I once saw it en masse, in southern Spain, lower down the upper slopes of the Sierra Nevada that are home to its tiny close relative A. purpureum, 418

this elfin endemic huddled into rock crevices and smothered in pinkish flowers. In cultivation it is invariably much laxer and loses its charm.

This is a recurrent problem, accentuated if high alpines are given too much loam and too little drainage. Many are scree or crevice plants, and their compost should consist mainly of fine grit and sand, laced with leaf-mould, perlite and a bare minimum of John Innes. The downy-leaved and steppe or dryland dwellers aside, they also benefit from scant overhead protection. The superior form of Pyrenean/Cordillera Cantabrican Draba dedeana (of which more later) selected by Eric Watson is THE ALPINE GARDENER

ROBERT ROLFE

BEAUTIFUL BRASSICAS

Draba dedeana, which if grown in the garden prefers a sunny, exposed position

at its best if grown in a trough or in a sunny, exposed position, while Turkish Ricotia davisiana (as a 1970 AGS show report reflected), ‘usually resembles a small portion of badly grown pink Arabis’, but at the April London Show of that year was exhibited by Peter Edwards as ‘a most beautiful crucifer’, the more remarkable for attaining this performance from a root cutting taken just a year earlier.

Names

within

names

Aubrieta is far and away the best known honorific genus in the family, referencing the French botanist Claude Aubriet (1668-1743). Among others, DECEMBER 2015

New Zealand Cheesemania (after Thomas Cheeseman (1845-1923), a Yorkshireman responsible for the ground-breaking Manual of the New Zealand Flora and several other coauthored works, includes C. wallii from fellfield habitats on South Island, occasionally seen in alpine houses. The double whammy, Greek Bornmuellera baldaccii (Joseph Bornmueller was a German taxonomist who travelled widely in the Balkans through to Iran from 1889-1929; Antonio Baldacci (1867-1950) was an Italian who collected extensively in the Balkans) doesn’t quite know whether it’s an Iberis or a Ptilotrichum, but is a pleasant 419

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JIM ARCHIBALD

Bornmuellera baldaccii, named after Joseph Bornmueller and Antonio Baldacci

enough Albanian and north-west Greek narrow endemic, which I once saw high on Smolikas in some abundance.

The monotypic Ianhedgea minutiflora, a squinny annual from Tibet through to northern India and parts of Central Asia at up to 4,200m, was named in 1999 for Edinburgh-based botanist Ian Hedge, acclaimed for his contributions to the floras of Turkey, Iran and elsewhere. It’s highly unusual to involve both christian and surnames when concocting a genus, whereas commemorating surnames in both generic and specific epithet coinings is routine, as with Dielsiocharis kotschyi from Iran and Turkemenistan, the first element referencing Friedrich Ludwig Emil Diels (for all that his 420

foremost contributions to science were made in the southern hemisphere), the species in question honouring Theodor Kotschy, a 19th century Austrian botanical explorer.

This is the plant that Paul Furse had a love-hate relationship with on his Persian travels, for ‘from six feet away [it] was indistinguishable from… [Dionysia odora]… one had to scramble up to every rock which had a glint of yellow with the forlorn hope of finding some Dionysia seed, only to find the crucifer in full flower, seedless, inextricable, with a smug and insolent smile all over its bright face’ (‘Some Iranian and Turkish Mountain Plants’, AGS Bulletin 1963, volume 31, pages 295-304). Long deemed THE ALPINE GARDENER

ROBERT ROLFE

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Tchihatchewia isatidea, grown from seed collected in Turkey by Jim Archibald

monotypic, it now has a sister species, D. bactriana, from Tadjikistan, formerly considered a constituent of Arabidopsis, a tongue-twister of a name that has tripped up several eminent lecturers.

The predominantly Chinese genus Solms-laubachia remembers the grandly named Count Hermann Maximilian Carl Ludwig Friedrich Graf zu SolmsLaubach (1842-1915), a German professor, botanical garden director and traveller. Another Count, this time of Russian extract, Pierre de Tchihatcheff (1812-90), who figuratively wore other hats, as a geologist and a politician, travelled around Turkey from 1848-63.

The spectacular cruciferous monocarp, Tchihatchewia isatidea, introduced a DECEMBER 2015

number of times – perhaps first by Peter Davis, then courtesy of Furse and Synge (1960), and infrequently afterwards, is a noble commemorative.

My seed of this last-named virtuoso soloist was from a Jim Archibald collection (‘not obviously close to anything else, anywhere’, Jim wrote), made just north-west of Aşkale in Turkey’s Erzurum Province at 2,000m, growing on ‘steep, loose, eroded shale slopes’. It was sown, as directed in the field notes, with the Honesty-like fruits uncleaned and inserted on their sides, rather than flat to the compost. This was a 2005 collection (it had also been offered from the same site 17 years earlier) that I uncovered while going through one 421

BEAUTIFUL BRASSICAS ROBERT ROLFE

of Jim’s packed seed rooms in 2010.

Already five years old, it took a further three years to germinate but a couple of seedlings resulted, appreciating the deep root run of a three-litre black plastic ‘Optipot’.

The largest rosette was clearly hearting up by the very early months of 2014, and then, in spring, very rapidly the central cluster of buds developed, with blooming commencing in the first week of April, reaching a peak during the last fortnight of that month.

Further flowers were produced for long after that ‒ throughout May and June in fact, the corymbs arching over as they elongated, as much due to the increasing weight of the side branches, which also sprawled, so that the final stages of the 422

performances were ungainly.

Fearing that this spike, by now almost 60cm long (and another more modest one, produced by a smaller plant) would break off, I staked them. And although my attempts at pollination were initially unsuccessful, either my technique improved or, more likely, some tiny insects attending the flowers did the job.

By August hundreds of pods, varying in size up to ones comparable with those of an Honesty, had formed. There was enough for me to sow several pots and to send some to the AGS Seed Exchange.

Smugly imagining that this would be a unique donation, I soon learned from AGS Seed Exchange Director Diane Clement that someone else had simultaneously contributed cultivated THE ALPINE GARDENER

ROBERT ROLFE

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Two Turkish species, Draba rosularis and, left, D. cappadocica, which have been confused in the past

seed. Even those of us who imagine we are abreast of who is growing what, and where, are often contradicted and have our horizons broadened, time and again. In February and March this year, a dozen seedlings germinated, their cotyledons Honesty-like.

A statute of limitations

This family is far too large to explore in its every facet, even confining discussion to alpine members already in cultivation or those that would make welcome additions. Therefore, I will first discuss Draba, afterwards conducting a globetrotting survey of just a few idiosyncratic others. Often endemic, or nearly so, they have been chosen in line with Roy Elliott’s parameters: ‘Guaranteed DECEMBER 2015

to afford us both pleasure and ease of cultivation in our rock gardens.’ Well, the first of these anyway ‒ in truth some have seldom or never been attempted.

Others have repeatedly proven tricky.

Appearing intermittently in seed lists, and in nurserymen’s catalogues, they deserve inclusion.

Draba data

This is the largest genus in Brassicaceae with, at the time of writing (the number keeps going up), getting on for 400 species. A few have been hived off, so that the annual, sometimes alpine Draba muralis, from much of Europe through to Greece, is now repositioned as a Drabella. Roy Elliott wrote in 1958 that ‘there is little variation in either colour 423

BEAUTIFUL BRASSICAS or form’. True perhaps of those cultivated at that time, but this is a statement that nowadays needs qualifying.

Certainly those of a cushion-forming persuasion, with yellow flowers held sessile or on short stems, predominate, and sometimes deceive, so that wellknown eastern Turkish/Armenian/ Transcaucasian D. polytricha has been passed off as Chinese D. yunnanensis in cultivation, while two other Turkish species, D. cappadocica and D. rosularis, have also been confused – at least until the former, ‘rather tighter and shorter stemmed’ as its collector observed, was introduced from Erciyas Dağ in 1984.

The further you delve, the more unexpected details come to light. How many reading this will realise that AGS and SRGC stalwart Ron McBeath is honoured not only in the singular Turkish Muscari now well-established in cultivation, but also in a yellow-flowered Nepalese Draba almost certainly not grown by anybody presently (and with a wonky spelling, D. macbeathiana), found at 5,500m on his productive 1983 botanical traverse of the Marsyangdi valley?

Even among the northern hemisphere species, it is easy to recognise a fair number without hesitation. As for those from the northern and central Andes, Roy’s strictures can be put aside, since from Venezuela to Peru, novelties predominate, representing the most bizarre developments of all.

Before reaching these, I would like to feature a quintet of white-flowered species, each deserving a place in the garden, either in the open or under glass. D. dedeana, already mentioned, 424

has been around longest and is seen at its most distinguished in the glossyleaved, broad-petalled form established by the late, renowned high alpine plant champion and hugely gifted cultivator Eric Watson up in Newcastle. Seedlings have inherited its virtues and should be grown in a sunny trough or raised bed, for in the alpine house inevitably the stems etiolate and its concise charm is forfeited.

Another European, also from the Pyrenees but extending eastwards to the Carpathians, including Austria in its territories (hence the specific epithet), D. carinthiaca is dwarfer still. Laxer variants can be up to 15cm tall yet, as presently grown, it barely reaches a fifth of that height. It is perhaps best used, again in a trough, as a colony rather than individually, given its very slow growth rate. Gentiana verna, Primula scotica and the smallest of the early-flowering, ‘kabschia’ saxifrages are recommended congeners.

If you can obtain it, D. sachalinensis from parts of Japan and Sakhalin is also worth considering. Its synonym D. grandiflora gives a fair indication of the floral impact, the petals to 8mm and the racemes many-flowered. I saw it one April, surrounded by the miniature, elfin Narcissus calcicola, and in perfect synchrony. In the heat of summer its greyish rosettes are inclined to shrink into insignificance, but if watered every so often it will endure and is at its best cascading between rocks – its preferred habitat is quoted as ‘rocky places in mountains’ in Ohwi’s Flora of Japan.

Hopeless in the open (its felted rosettes rot in summer and even more quickly in THE ALPINE GARDENER

ROBERT ROLFE

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The Japanese Draba sachalinensis is at its best cascading between rocks DECEMBER 2015

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DENNIS GREEN

winter), the 1996 Russian introduction D. ossetica is classified in Series Mollissimae (along with D. mollissima and D. longisiliqua) and is fit company for either of these in the alpine house, where it will occasionally hybridise. To date, though, the few chance seedlings have not rivalled the glossy purity and sophistication of the mother plant.

As with so many of the other woollyleaved species, from the Caucasus and further west, D. ossetica sometimes fades away in winter and even the most skilled growers have suffered repeated losses, especially when the weather takes a severe turn. Cold is clearly the enemy, for cushions die away on the side closest to the glass. The half facing the central aisle of the alpine house is typically undamaged. Nevertheless, it has on occasion been grown to a diameter of 30cm, for all that more silver in leaf, yellow in flower D. longisiliqua (also from the Caucasus, first sent back by Martyn Rix 20 years earlier) outdoes it on this score. It’s the only potted plant that I could barely manhandle ten yards, soon realising that a wheelbarrow would be necessary to facilitate its return journey, along with help in lifting it back into the plunge bed.

There are white species in the Americas too, north and south, D. oreibata the most rewarding of those attempted to date. I’m sure it has been offered on other occasions, but my slight knowledge goes back to a 1987 seed collection made in Charley Canyon, Idaho, where it grows in part-shaded limestone crevices at around 1,900m. Lauded by its selector as ‘a fabulous new introduction’ with ‘especially hairy grey cushions, bearing

The American Draba oreibata

large, white, very short-stemmed flowers’, it was grown to a superlative standard by Una Green, a very fondly remembered, engagingly droll and extraordinarily skilled exhibitor who routinely grew notoriously difficult alpines to a large size without forfeiting their salient qualities. Their pristine condition (the least hint of a fading flower was anathema to her) and setting apart, her plants looked like the very best of those encountered on their native mountains. I doubt this species has ever been better grown, but am bound to say that it might well have been better photographed, for all that I treasure the slide she kindly provided. Long thought restricted to five Idaho counties, this THE ALPINE GARDENER

ROBERT ROLFE

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Draba longisiliqua, introduced from the Caucasus by Martyn Rix in the 1970s

changed when in 1991 a larger-leaved adjunct from over 3,000m in the Snake and Toiyabe ranges of Nevada, 480km distant, was described as var. serpentina.

It has since been shown to have a different chromosome count and some authorities consider it a species in its own right.

Very few of the Andean species have impinged on gardeners’ consciousnesses. In the absence of an improvident, altruistic, monomaniacal maverick seed collector, nothing will change. The genus shows its greatest quirks in the central and northern ranges, where idiosyncratic, sometimes columnar rather than cushion-forming examples occur. It’s not that there aren’t DECEMBER 2015

sufficient lures, from the subshrubby D. matthioloides, with flowers to 9mm diameter of ‘bright orange to glowing rusty red, green-centred’ (AGS Encyclopaedia: it can also be yellow, and purple in subsp. saundersii from La Libertad Province at 4,430m), to D. werffii, true blue in some phases and described from Arequipa Province in 2009. Don’t get too excited: the latter’s blooms are minute. But the average rock gardener has quite enough Eurasian representatives of proven worth from which to choose.

Tropical alpines tend to be recalcitrant and will receive only a very small welcoming party, no matter how different or distinguished they might 427

BEAUTIFUL BRASSICAS be. In captivity they often sulk. In an article of this nature, on the other hand, it would be negligent not to give a nod to a few of them. By way of a 25-yearold correction, I’ll start by invoking the name D. steyermarkii, described in 1991 from the chilly paramos of Las Cajas (Azuay, Ecuador) at 2,7004,400m, a sub-shrubby, lilac or purpleflowered species that blooms the year round, once known as D. violacea var. lehmanniana, the only identity available when I encountered it on a June visit to that region the year before. The oblong leaves and small seeds help distinguish it from its former annexation.

Following my 1990 encounter I flew home at first over Venezuela, gawping out of the aircraft window over a series of spectacular mountain ranges that culminate in the 500km long Sierra Nevada de Merida, close to the Caribbean where, the year before, David and Anke Wraight made a JanuaryFebruary sortie, offering four Draba accessions that have not been replicated since. Think you know what the genus holds in store: think again! How about Draba ? arbuscula WR 8912, a ‘dense, congested little bonsai-like shrublet’ from granite screes at 4,600m, or Draba sp. 8918, from 4,200m, ‘forming columnar woody trunk to 30cm tall … [with]… linear leaves; flowers large, drooping, Allium-like, a fascinating and bizarre addition’.

Arguably most distinguished of them all is D. chionophila, occurring at the highest altitudes in these mountains, to almost 4,600m. Up to just over 20cm tall in bloom, it can yield as many as 500 yellow flowers per panicle and exhibits 428

an extraordinary root range, the lateral ‘feeders’ spreading up to 2.5m from the crown in order to source nutrients and moisture, which must surely constitute a record for the genus, pro rata. An old Kentish word, ‘spronky’ (meaning full of roots’), is apposite. Growing in often very cold areas where night-time temperatures plummet the year round, it counteracts this by establishing a stout taproot that resists frost-heaving, anchoring it into the subsoil, then permeating this with the just mentioned lateral roots. Such taxa are deduced to have evolved from repeated northsouth migrations from North American ancestral species, and also from Asian progenitors that migrated via the Bering Bridge. They have since speciated, distancing these purported ancestors.

Draba takes on various prefixes in the southern Andes, of which Xerodraba is the best known. Martin Sheader writes about these and others in an article following this one. As for North America, I’ve alluded to a few members of the family but readers are referred to the spring 1990 issue of the Bulletin of the North American Rock Garden Society, largely devoted to Brassicaceae from that subcontinent.

Notothlaspi in New Zealand

While skirting the southern hemisphere, it is mandatory to mention Notothlaspi rosulatum, the penwiper plant. Up to 25cm tall in fruit, with rosettes to 8cm across, it seldom attains such dimensions in cultivation. More or less monocarpic, it is reluctant to set seed, and with the flow of seed from its native New Zealand now reduced THE ALPINE GARDENER

PETER ERSKINE

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Notothlaspi rosulatum, a transient plant seldom found blooming in large numbers

to little more than a trickle, it is very seldom encountered away from home.

In his Field Guide to the Alpine Plants of New Zealand (1968), John Salmon observed that it ‘grows on screes among the finer debris which is partially stabilised. Found on the east side of the Southern Alps from Marlborough to South Canterbury between 8001,850m… The highly fragrant flowers, similar to those of N. australe, occur during December and January on a stout stalk. Penwiper is a transient plant, always difficult to find and seldom occurring in large numbers in any one area for more than two or three years. It probably takes two years to mature, after DECEMBER 2015

which it flowers, seeds and dies. Even tiny plants not more than 3mm across may bear a few flowers’.

I’ve grown it to flowering size three times, most successfully from a Steve Newall gathering made in the St Arnoud range. Four of these flowered early one May, as single crowns and in unison, surrounded by young plants of Chionohebe pulvinaris, another characteristic plant of South Island screes and fellfields. Decapitation isn’t at face value a sure means of promoting longevity, except when it comes to certain plants. Removing a flower spike early on appeared to work, for two shoots were sent up from the stump…

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Iberis candolleana from Mont Ventoux in southern France

which produced a miserly two flowers apiece, a month later, before the plant joined its sister seedlings in the land of the deceased.

Aside from its close relative, the perennial N. australe, there are suggestions that a third species remains undescribed. I suspect that two names from the 19th century, N. hookeri and N. notabile, are responsible for this conjecture, though the status of both is unresolved. What can be said with certainty, following recent research, is that the name Notothlaspi is unfortunate, for the genus is not closely linked to Thlaspi.

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Iberis and Matthiola

Again, this is an arbitrary choice of representatives, but given their respectable track records, they are well worth trumpeting. Since childhood (my godmother owned a steeply sloping garden, part-terraced with limestone rock work) I’ve enjoyed the dazzling white of easily grown, easily hacked-back to a convenient size Iberis sempervirens, nowadays available in a dozen or so forms and staunchly perennial in all of these. But it’s the shorter-lived species that I favour. These typically flower themselves into oblivion and do not set seed reliably unless cross-pollinated, so should be grown in multiples if you wish THE ALPINE GARDENER

ROBERT ROLFE

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Iberis spathulata above Nuria in the Pyrenees, northern Spain

to maintain stocks. Very good advice, if only I had followed it.

Of these transients, first mention should surely go to I. pruitii, except that ‒ despite its continued usage in authoritative publications ‒ it is now given as a synonym of I. carnosa. The Flora Europaea entry, under the first coining, adds: ‘Many variants have received specific names and some appear to be of restricted distribution.’

With good reason! In particular I regret the ‘lumping’ of I. candolleana from Mont Ventoux, a refined, pinkflushed expression that is isolated from other examples of I. carnosa/pruitii, and should not be saddled with the DECEMBER 2015

misapplied group name that currently confuses the position. Recent listings admit that the make-up of the genus is more complex than once conceived, so that Russian I. oschtenica, described in 1953, is deemed a valid taxon. This westernmost Caucasian endemic (Gentiana oschtenica advertises the same locale) has been grown over the past decade, its probable, principal source being the 2000 Midwest Plant Collecting Collaborative Expedition to Georgia. Another boom and bust plant: it is apt to flower spectacularly in late spring, then fizzle out. My limited experience suggests much the same for high Pyrenean I. spathulata, from 431

BEAUTIFUL BRASSICAS the French-Spanish frontierlands at up to 2,800m, seldom more than 15cm across, and mainly monocarpic. In late June, it was frequent high above Nuria in the easternmost Pyrenees, the scree all around dislodged occasionally by whatever version of the chamois that lives there.

Spain and adjacent North Africa are equally strongholds of Matthiola, also known from much further afield, in Afghanistan most enticingly, where yellowish-flowered M. afghanica occurs intermittently at up to 3,000m, while M. codringtonii (named after the grandee gardener-adventurer John Codrington, one assumes), from tufa cliffs at 2,800m in Bamian Province, flaunts rose-pink flowers 4cm in diameter above hummocks of white-tomentose, congested foliage.

Discoveries continue to be made, among them M. trojana (2006), yet another endemic from north-west Turkish Kaz Dağ, at 1,550m, following on from the idiosyncratic dwarf thrift Armeria trojana, described as long ago as 1970 but only fairly recently in cultivation. Known far longer, dating from the early 1930s, southern European M. fruticulosa has been split into a number of races (and has been hitherto ascribed to Hesperis and Cheiranthus).

Its most pervasive alternative guise is surely M. tristris, the so-called sad stock, orthodoxly yellow to purple-red, but ‘chocolate-black’ in an example from ‘near the Spanish village of Velez Rubio’, reported by Dwight Ripley in AGS Bulletin volume 41, page 126.

The version I grew for a decade or more, lavender-flowered and duskily fragrant, 432

was probably subsp. valesiaca, recorded from parts of Spain and the Pyrenees, the southern Alps and the Balkans at up to 2,000m, mainly on limestone, as in the case of our photograph. With appealingly greyish-tomentose foliage, it has a suckering growth habit and steadily colonises by vegetative means as well as by seeding gently across the sharply drained areas it favours. It is easily propagated by lifting a portion or taking ‘Irishman’s’ cuttings. At its best in May, it is a worthwhile acquisition.

Sun-loving Heliophila

Matthiola extends its reach down to southern Africa, where there is one native species and a couple of incomers.

Other outliers of the family, hypothesised to have evolved via European or Asian corridors long, long ago, are too little known in horticulture. Some have become naturalised, such as watercress; others are endemic (Aplanodes and Chamira).

The most numerically and horticulturally significant contingent, Heliophila, has around 90 species, from annuals to hardy perennials, including shrubby members and a divergent climber, the non-hardy H. scandens, along with annuals and lowgrowing perennials. The few from the Eastern Cape and further north in the Drakensberg reach the highest altitudes.

The widespread H. rigidiuscula gets to 3,350m but is sometimes found at only 100m: knowledge of the provenance is important when attempting to grow this and others; H. alpina ‒ a 15cmtall perennial that colonises screes and steep, grassy slopes ‒ is more consistently THE ALPINE GARDENER

JIM ARCHIBALD

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Matthiola fruticulosa subsp. valesiaca

upland in its haunts, with an altitude banding of 2,650-3,350m; and Hilliard and Burtt’s enticingly christened H. formosa attains a respectable 1,9502,950m.

The overwhelming majority are from the Northern and the Western Cape and these, too, are often mountain plants.

The annual/biennial H. coronopifolia is occasionally listed by British nurseries and seed is easily obtainable. Its common name, blue flax, gives some idea of its appearance, though the flowers remind me most of Veronica fruticans in magnified form (they can be up to 12mm across), right down to the accentuated whitish eye. Our photograph overleaf, DECEMBER 2015

taken by revered photographer the late Colin Paterson-Jones, shows it growing in happy association with Cotula turbinata among the granite hills above Langebaan on the Cape west coast.

Whether from such localities, or from its highest occurences at around 1,800m, it is best sown annually, and started off under glass if sown in the autumn.

Germinating well and quickly, within a week if the weather is mild, plants seldom reach the 60cm that optimum conditions in the wild can induce, but grow easily in a raised bed in full sun.

Found from Namaqualand down to the Western Cape, this is a springflowering species (August-October).

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BEAUTIFUL BRASSICAS COLIN PATERSON-JONES

Blue flax, Heliophila coronopifolia, with Cotula turbinata on the Cape west coast 434

THE ALPINE GARDENER

COLIN PATERSON-JONES

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A white form of Heliophila juncea on the Katbakkies Pass

Shrubby H. juncea, whose distribution is analogous, from the Kamiesberg all the way south to the Langkloofberge, which rise steeply above the small town of Uniondale not far from South Africa’s famed Garden Route, also starts off in August but in some places is still in display come December.

Heliophilas usually have blue flowers, but some species can be white, pink, even purple ‒ or all of these possibilities in H. juncea, including changes from one shade to another as the 8-20mm long petals age. First described as a Cleome, for many years this species was placed in a separate genus, Brachycarpaea, but a 2005 revision incorporated it and four others within Heliophila.

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Not all of those familiar with the plant are convinced. Rachel Saunders (her and husband Rod’s Silverhill Seeds catalogue is easily the best source of the genus – visit www.silverhillseeds.co.za) tells me that ‘Brachycarpaea seeds are more or less round and hard, whereas Heliophila seeds are flat little disc-like things’.

Between 25cm and 1m tall, it typically forms an element of the fynbos on rocky sandstone slopes at up to 1,700m, with wand-like, resilient stems that are fireresistant.

Flowering is often profuse after a ‘burn’ has engulfed a population. This purge helps to explain why plants have been described as devoid of foliage. They are not ordinarily so, with the linear-oblong, 435

BEAUTIFUL BRASSICAS 1.5-5cm long leaves alternately arranged up the branches.

Hermannia stricta, Panayoti Kelaidis’s valuable 1994 introduction from the Kamiesberg, has settled down as a usefully long-flowering alpine-house plant. In its dwarfer forms, there is no reason why Heliophila juncea should not join it. Thanks to the generosity of Dee Snijman, we are able to publish a further two images taken by Colin Paterson-Jones, the first an albino form of H. juncea seen on the Katbakkies Pass (Kouebokkeveld, Western Cape) in late August. The snow-line here is at 1,000m and in some years the entire range is covered. Photographed at much the same time of year, but on the Skurweberg (above Skittery Kloof, also in the Western Cape), a mauve-blue form puts on a tremendous show, as seen on the opening two pages (408-409) of this feature. It grows with the annual, orange but black-centred Arctotis fastuosa, available from Chiltern Seeds and other sources.

A few Chorisporeae

Brassicaceae is subdivided into an assortment of tribes, some fairly recently coined, that serve to group genera with shared characters. Chorisporeae, for example, is an assemblage of mainly Central Asian plants of which the largest genus is Parrya, the umbrella name derived from far smaller Chorispora.

Of the latter, I’ve grown a couple, the first of them C. macropoda, which Jack Drake offered in his 1975-76 supplementary list, from seed collected by the 1971 Wye College Expedition in Afghanistan (its full distribution is much 436

wider, stretching from Kazakhstan to Xinjiang). The catalogue entry decribed it as ‘very choice’ and suggested ‘scree or light, gritty soil’. Grown in the latter, in a clay pot within a cold frame, it survived a respectable four years, performing twice, both times in late April. Yet in its native mountains, where it can be found at up to 4,500m, June through to August is the main flowering season. The somewhat crinkled flowers, arranged in dense racemes, are light yellow. Those of my plant were attractively marked with brown around their eyes, a feature not mentioned in the descriptions I’ve read.

With a rather similar range but easily told apart because of its different colour, and the fact that the larger flowers are borne singly on short pedicels, C. bungeana has been maintained in gardens on occasion, aided by its ability to set seed in exile, this countering its short-lived tendency. Forming a tuffet obscured by the pink or purple flowers, 3-4cm across or more, for such a small plant it also has very prominent fruiting pods, narrowly cylindrical and up to 3cm long. Older members might recall that seed brought back from the Tien Shan by Ray Hunter was the source of the plant shown by RBG Kew to the Joint Rock Garden Plant Committee in 1982, when it was noted that plants at the Cambridge University Botanic Garden had persisted for a while outdoors. They must have been corralled by slug pellets, for molluscs are very fond of this plant.

A modest black and white illustration was published in AGS Bulletin volume 50, page 326. In vivid contrast, we are most grateful to Dr Petr Kosachev at Altai State University for allowing us to THE ALPINE GARDENER

PETR KOSACHEV

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Chorispora bungeana in the Altai Republic’s Ulagansky district in late June

use his superlative photograph, taken in the Altai Republic’s Ulagansky district in late June, one of the species’ more northeasterly locales. The habitat is given as ‘stony tundra’, which clearly also suits Eritrichium villosum, photographed at the same time, forming truly spectacular clumps that put E. nanum, the King of the Alps, to shame.

The seeds of Chorispora are unwinged and housed in scaled-down, French DECEMBER 2015

bean-like pods, while those of Parrya are broadly winged. Seed morphology is critical in the classification of the family, and an essay could be written about the most ornamental pods, some inflated ‒ the North American genera Lesquerella and Physaria excel ‒ others wafer-thin but much magnified, as in Lunaria annua. The general absence of stem leaves is diagnostic.

Their principal haunts are also Central 437

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Parrya fruticulosa from Uzbekistan, Afghanistan, Kyrgyzstan and Tajikistan

Asian ‒ the Pamir-Alai, north-east to the Tien Shan ‒ but they reach China, and even extend to the Arctic in the case of Parrya nudicaulis, forming a link between north-easternmost Europe and Alaska/northern Canada with three other North American species.

P. rydbergii is located as far south as Wyoming and Utah.

Now I’d like to correct several misconceptions. Firstly, it’s true that yellow-flowered, western Chinese P. forrestii was described as such, in 1914 (it was illustrated under this guise in AGS Bulletin volume 56, page 25) but it has now been reassigned to Erysimum. This is sensible: Parrya are predominantly 438

white or pink in all shades, rarely brownish, but never aureate/yellowish.

Secondly, if you have raised seed of a Neuroloma (it’s most unlikely that you will have obtained plants by any other means), or else a Pseudoclausia, you should change the labels to read Parrya, in line with the most recent treatment (Ihsan A. Al-Shehbaz & Dmitry A. German, ‘A synopsis of the genus Parrya (Brassicaceae)’, Kew Bulletin 2013, volume 68, pages 457-475).

Ignore the name P. kokandica, despite its previous usage in this journal (volume 75, page 98, and various other references). Apply the specific epithet to a Rosa of that ilk, a rarely grown Morina, THE ALPINE GARDENER

ROBERT ROLFE

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Leiospora pamirica prefers a frugal, very gritty compost

even a species of mealy bug among a few other unpleasant insects legitimately described under this allegiance, but do away with the Parrya false identity, not even credited as a synonym in the definitive 2013 revision. The earliest usage would appear to be Josef Halda’s 1992-93 seed list, under the collection number JJH 209365 (‘from the eastern Pamir, 4,800m, fleshy dentate leaves, white or pink flowers’). Around 30 per cent of the genus can be found in Tajikistan, from where this introduction was sourced. In all likelihood it should be reassigned to P. fruticulosa, notable for its broadly ovate, purple to lavender, flounced petals, notched at the apices. It DECEMBER 2015

was first described from Uzbekistan at 800-2,150m but is also recorded from Afghanistan, Kyrgyzstan and Tajikistan.

Alan Furness’s plant, exhibited at the 2006 North Midland Show, came via Betty Lowry from a Halda introduction and represented a benchmark when it comes to the cultivation of the genus.

There is, it should be added, an Arabis kokandica Regel (and also, confusingly, an A. kokonica Regel & Schmalh), quite apart. As a grace note one should add P. schugnana, a viscous-leaved, whiteflowered species, also from Tajikistan, grown at RBG Kew in the 1980s and soon afterwards by me from a separate source. It’s by all accounts a cliff-dweller.

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BEAUTIFUL BRASSICAS Truly tedious to remove all the dead foliage in winter but the reward comes in spring, not least from the perfume that this and others exude.

Leiospora is distantly related to Parrya, distinguished primarily by the production of seed heads that detach easily from their stalks and by its sessile stigmas and independent ‘petal’ lobes. A much smaller genus, just six species are recognised at present, only half of these offered in seed lists within the past 20 years, as far as I can trace. The present designation L. pamirica dates from 1972 (it was first described as a Parrya 50 years ago). It’s another alpinehouse plant of self-limiting, specialist appeal, found at up to 5,500m on ‘dry stony plains and rocky cliffs’ from Kashmir and Tajikistan to Xinjiang and Tibet. It produces up to seven flowers from each of its small but broad-leaved, sometimes densely pubescent rosettes (those illustrated here are at the other, almost glabrous extreme). Capable of flowering even in its first year, it is relatively deeprooted, preferring a frugal, very gritty compost, and has appeared just once or twice on the showbench (the illustration is of a Halda introduction, grown by George Young).

S o l m s - l a u b a c h i a

This is one of the few genera mentioned in which the number of species has recently been reduced rather than supplemented, in this case leaving nine, all endemic to the mountains of western China with the exception of Solms-laubachia platycarpa, also known from Bhutan and Sikkim.

Several were described from material sent back by George Forrest a century 440

ago. The spelling should be hyphenated, as per its progenitor, although this rule hasn’t always been applied.

Of especial interest for members of the AGS, a collection made on Beima Shan in 1994 during the first stage of the Society’s China Expedition (ACE 855) was recognised by leading Brassicaceae expert Ihsan A. Al-Shehbaz and his Chinese colleague Yang Guang as a new species, S. gamosepala. This has a much smaller calyx than any other and smaller flowers, too, consistently white rather than the pinkish, delicate purple or blue hues that otherwise characterise the genus in China. It was named in 2001.

S. zhongdianensis followed in 2005, repositioning Yunnanese examples of a taxon previously grouped under the name S. minor, whose type and misjudged specimen is now known to represent S. pulcherrima. (The county of Zhongdian has been rebranded Shangri-La. In a further twist, a quite separate, monotypic Brassicaceae genus has been described as Shangrilaia.)

Identification can be a ticklish business, relying on whether or not the sepals are united; the presence or otherwise, the nature and direction of the foliar hairs; and the shape of the seed pods. Leaf sizes and outlines overlap from one species to another, so that in the case of S. pulcherrima, only by scrutinising the petioles (non-ciliate) and the leaf surfaces (glabrous or sparsely pubescent) is it possible to separate it from pilose S. linearifolia with any confidence. All rather highfalutin. The species co-occur on, for example, Da Xue Shan, where our photograph was taken at 4,500m.

As intractable as they are beautiful, THE ALPINE GARDENER

HARRY JANS

BEAUTIFUL BRASSICAS

Solms-laubachia linearifolia on Da Xue Shan at 4,500m DECEMBER 2015

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BEAUTIFUL BRASSICAS HARRY JANS

Solms-laubachia linearifolia in close-up

several of the species have nevertheless been coaxed to flowering size in cultivation, yet have proved extremely difficult to maintain in good health, never mind propagate. Once in a while a seedlist offers another one, most recently S. xerophyta. The ACE venture found up to three species growing more or less together elsewhere, and indeed that trip also encountered S. zhongdianensis on the mountain just mentioned (ACE 1704), making the total count there as well at least three. The majority of those from Yunnan also occur in Sichuan, while S. retropilosa (our image is from Beima Shan at 4,650m, growing in association with a dwarf Rhododendron) is native to both provinces and to Tibet.

In 2010, Dmitry German and Al442

Shehbaz merged two other rather obscure genera, Phaeonychium and Eurycarpus, sizeably bumping up the distribution and head count for Solms-laubachia.

Details are given in ‘Nomenclatural novelties in miscellaneous Asian Brassicaceae (Cruciferae)’ published in the Nordic Journal of Botany, volume 28, pages 645-651.

Typically inhabiting limestone screes and rocky outcrops at up to 5,200m, exceptionally 5,700m, the Chinese species attempted in cultivation so far pose the same difficulties as sundry other plants from the same terrain and similar altitudes. Sampson Clay’s advice, given in 1937, to try them first in an alkaline scree mixture with a pinch of humus, but if this didn’t meet with success, then THE ALPINE GARDENER

HARRY JANS

BEAUTIFUL BRASSICAS

Solms-laubachia retropilosa growing with a dwarf Rhododendron at 4,650m

‘in anything and everything, indoors and out’, is lacking in precision, but recipes for enduring success have been conspicuously absent since then.

All the more reason to publish images taken in their homelands, bringing their beauty (but not, unfortunately, their beguiling fragrance) to the attention of readers, most of whom will not have travelled to China and elsewhere to savour these at first hand.

Some wild plants are wholly likely to remain as such – wild rather than tamed.

Having acknowledged this, there is a vicarious pleasure to be had in surveying them en bloc, whether from the remoter parts of Patagonia, the Altai, or sundry high passes in southern Africa that lie off the beaten track. The intention has DECEMBER 2015

been to meld these with others that can be grown easily, or if not quite so readily, then at least satisfactorily from time to time, demonstrating the often overlooked appeal of a wide assortment of plants that has a far more realistic claim to the designation ‘alpine’ than many others loosely described as such.

An article of this nature relies on considerable outside help, and I would particularly like to thank Jenny Archibald for the use of photographs taken by Jim Archibald, Dee Snijman for the use of photographs taken by Colin Paterson-Jones, Rachel Saunders, Dr Petr Kosachev, Peter Erskine, Kit GreyWilson, Tony Hall and Harry Jans.

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The tiny Eudema monantha forms loose mats on fine scree

Searching for Patagonian brassicas and the challenges of growing them at home 444

T

hink of choice Patagonian rock plants and perhaps rosulate violas, benthamiellas, calceolarias, oxalis and verbenas (in the broadest sense) spring to mind, but how many brassicas would you be able to list?

Within Argentine Patagonia, 47 brassica genera and 132 species have been recorded, though a good number of these are non-native accidental or agricultural introductions. Twenty-two genera are endemic and it is primarily this group that contains potentially worthy plants for the rock garden. Very few of these species are in cultivation, but a few would be well worth trying should seed ever become available.

THE ALPINE GARDENER

BEAUTIFUL BRASSICAS

Eudema hauthalii has cream or pale yellow flowers with recurved petals

To complement the previous article, Martin and Anna-Liisa Sheader look at Patagonian brassicas and discuss their performance in cultivation The genus Eudema contains two species, both attractive and probably growable, but found in very different habitats. They are plants of the extreme south, so, in the wild, would experience cold winters and usually cool summers.

The first species, E. monantha (syn.

Xerodraba monantha), is tiny, forming DECEMBER 2015

a loose mat among fine scree on exposed ridge tops at about 800-1,000m elevation. The flowers are intensely eggyolk yellow and sit at ground level among the leaves. We have grown and flowered this species, but in cultivation, the leaves were larger, hiding the flowers. A leaner diet and more light are probably needed to succeed with this one. In habitat it grows with Hamadryas delfinii, Bolax caespitosa, Oxalis enneaphylla and Nassauvia lagascae.

The other species, Eudema hauthalii, occurs on mountain slopes and ridges beneath areas of snowmelt, where the ground remains moist throughout spring and summer. Where conditions 445

BEAUTIFUL BRASSICAS

Lithodraba mendocinensis has proved difficult to flower in cultivation

are suitable, E. hauthalii can form sizeable cushions or mats, which, in spring, are covered by large cream or pale yellow flowers with recurved petals.

In the wild it grows with plants such as Caltha sagittata, Nassauvia magellanica, Saxifraga magellanica, Hamadryas sempervivoides and Valeriana macrorhiza.

The genus Lithodraba has a single species, L. mendocinensis. This is a plant of northern Patagonia, with its distribution extending north into the wine-growing province of Mendoza. It grows among rocks at 1,700-3,500m and forms hard cushions which, in spring and early summer, can be completely 446

covered by small white flowers. We grew this from seed supplied by Anita Flores and John Watson some years ago. It survived well in a pot and grew slowly in a raised bed outside but, over about ten years, steadfastly refused to flower.

In habitat, other crevice plants growing with this species include Junellia spissa, Benthamiella graminifolia and Fabiana foliosa.

The related genus Xerodraba contains five species, all to be found in the south of Patagonia. They form tight cushions or mats on mountains slopes or in rocky steppe habitat, and are arguably the most attractive of the Patagonian brassicas. Three species, X. pectinata, X. THE ALPINE GARDENER

BEAUTIFUL BRASSICAS

Xerodraba patagonica is a plant of windswept grassy or stony ridge tops

patagonica and X. pycnophylloides, were introduced into cultivation by Flores and Watson, and there have been several more recent introductions.

We have had mixed success with these.

All are slow growing and eventually, after several years, produce flowers but not with the foliage-covering exuberance that they do in the wild. X. patagonica and X. pycnophylloides both have white to pink flowers emerging from tight rosettes, the former being a plant of windswept grassy or stony ridge tops at 700-1,100m, and the latter, which has much smaller leaf rosettes, is characteristic of steppe and coastal habitats up to about 900m.

DECEMBER 2015

X. pectinata and X. lycopodioides have slightly looser rosettes than the previous two species and have relatively longer leaves with pectinate (comb-like) hairy margins. X. pectinata has creamy yellow flowers and is found on mountainsides and high ridges, often with X. patagonica. X. lycopodioides is white to pink flowered and grows in rocky steppe habitats. We have yet to find the fifth species, X. chubutensis, on our travels.

Sarcodraba subterranea is a beautiful high mountain species we first found in Torres del Paine National Park (Chile) in 2011 – a new park record. It has since been recorded on the Argentine side of the border in Los Glaciares 447

BEAUTIFUL BRASSICAS

Clusters of flowers emerge from the fleshy leaf rosettes of Sarcodraba subterranea

National Park. This is a species of high, bare, windswept ridges, where it grows with plants such as Benthamiella nordenskjoeldii, Hamadryas kingii and Oxalis enneaphylla. From rosettes of glaucous, fleshy leaves appear clusters of up to nine white flowers with contrasting fleshy, pink sepals. This would be an interesting plant to try in the alpine house, should seeds ever become available.

There are eight species of Menonvillea in Argentine Patagonia. Of the perennial species, Menonvillea nordenskjoeldii, native of southern Patagonia, is perhaps the most attractive. It is a plant of rocky screes at altitudes of 900-1,700m. At 448

snowmelt, water seeps or flows through the scree habitat, a challenge for those hoping to recreate similar conditions in cultivation. In various parts of its range, M. nordenskjoeldii shares this habitat with other choice scree species such as Combera paradoxa, Viola sacculus and Oxalis loricata. Shoots push to the surface in spring from subsurface rhizomes, giving rise to many-flowered inflorescences of white or pink flowers.

The final genus we consider here, Onuris, comprises four species in this region, all to be found on rocky or sandy mountain slopes and on exposed ridges.

The southern species, O. hatcheriana, forms a tight mat or cushion with white THE ALPINE GARDENER

BEAUTIFUL BRASSICAS

Above, Menonvillea nordenskjoeldii, the most attractive of the eight species of the genus found in Argentine Patagonia Right, Xerodraba pectinata, found on mountainsides and high ridges

DECEMBER 2015

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BEAUTIFUL BRASSICAS

A quartet of Onuris species.

Above, O. spegazziniana.

Left, O. hatcheriana.

Opposite above, O. graminifolia.

Opposite below, O. papillosa

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THE ALPINE GARDENER

BEAUTIFUL BRASSICAS

or pink flowers, and with inflorescences held just above the foliage. The other three species, O. spegazziniana, O. papillosa and O. graminifolia form looser mats, with inflorescences up to about 10cm above the foliage. As with O. hatcheriana, the flowers are white or pink. These are untried in cultivation.

There are a few other cushion-forming mountain species that, from their descriptions, appear to be of interest – for example Delpinophytum patagonicum, Skottsbergianthus collobanthoides and S. sorianoi – but we have yet to find these on our travels.

DECEMBER 2015

451

SALIX X BOYDII

It is among the most distinguished of truly dwarf shrubs, but the identity of readily grown Salix x boydii has long been the subject of conjecture. David Tennant, who has studied the genus extensively in the field and has contributed the section on mountain willow hybrids to the recently published Hybrid Flora of the British Isles (C.A. Stace et al), discusses its history and re-evaluates the parentage of this very popular Scottish willow

S

alix x boydii was first described and published under the name Salix boydii by the Reverend Edward F. Linton in his monograph The British Willows (1913). The author, the leading British salicologist of his time, was sent specimens of the willow for an opinion

by Dr William Brack Boyd, a farmer, botanist and horticulturist of Melrose, Roxburghshire, who cultivated it in his garden.

Boyd suggested that it was a hybrid and proposed that the parentage might be Salix lapponum x reticulata. Linton did not wholly agree, arguing that some other parental influence was needed to account for several of its characters.

But ‘for want of a better explanation’, surprisingly he published this parental combination.

Boyd had told Linton that he discovered the willow in Glen Clova, Angus.

Comments in his correspondence dated 1913 (to be found in the Natural History Museum, London) suggest that only a single seedling plant was found, which he probably dug up and transferred to his garden.

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Unravelling the mystery of Boyd’s willow The relevant letter also implies that the collection took place in 1905 or 1906, and that he had visited the site only once. However, neither date is correct, for several herbarium specimens in the museum, which Boyd had sent to Linton, are dated 1902 and their maturity is indicated by the presence of catkins (often borne freely and of the ‘pussy willow’ type, appearing with the new foliage in April or early May). The actual date of its discovery is therefore almost certainly before 1900, although correspondence giving a precise date has not been traced.

Another interesting observation made THE ALPINE GARDENER

SALIX X BOYDII

Since its discovery in Scotland at the turn of the 19th century, there has been much debate about the origins of Salix x boydii

by Boyd was that also plentiful at the site where he said he had discovered S. x boydii were the species he deduced as its parents, namely S. lapponum and S. reticulata. Although several willow DECEMBER 2015

species are now known to occur there, S. reticulata is not one of them (and was very doubtfully present even in Boyd’s time), the nearest known locality being around one kilometre distant.

453

SALIX X BOYDII The site has been searched many times since Boyd made his discovery: nothing identical to S. x boydii has been found there again or anywhere else for that matter. On the other hand, there is no other evidence that Boyd did not find the willow where he suggested and too much significance should not be placed on his comments, which may have been due to an inaccurate recollection or a misinterpretation of his meaning.

Nonetheless, the slight doubt raised does invite other explanations.

At the site where Boyd said he had collected S. x boydii, one of the other hybrids still there today is S. x obtusifolia Willd. (S. aurita x lapponum). This is a variable hybrid, at this particular site bearing some resemblance in its foliage to that of S. x boydii (some other characters are divergent). This could either strengthen Boyd’s declared provenance for his novel hybrid or provide an alternative possible explanation.

There is a slight chance that he actually collected a form of S. x obtusifolia instead, which subsequently crossed with another willow or willow hybrid in his garden. In any mixed Salix collection, new plants are liable to appear spontaneously from seed next to their parents and then develop rapidly.

This has occurred in my own garden, S. x boydii having crossed naturally with other willows to produce multi-parent hybrids. It is well known that Boyd produced many hybrids deliberately in his garden at Faldonside, Melrose.

Those involving genera such as Saxifraga (these mainly produced by his older brother John at Cherrytrees, the 454

family home), Dianthus, Primula and Galanthus remain highly prized even now, a century later. And certainly he grew other willows, collecting widely in the European Alps and adding these and other plants to his garden.

In 1891, when he moved house to Upper Faldonside, Boyd transferred many of his plants to the new garden.

Although it is not entirely clear whether S. x boydii had been grown in his old garden, if it was there is the remote possibility that an error occurred when the willow collection was moved.

Another plant discovered by Boyd, Sagina boydii, also has an unresolved origin. Boyd was unable to remember where it came from, and in Mountain Flowers (Collins, 1956) John Raven considers it the greatest mystery in the annals of British botany. Now recognised as a unique form of S. procumbens, it has never been found in the wild state since.

Willow hybrids are notoriously difficult to identify. This inscrutability arises from the fact that although only six truly montane (i.e. alpine or subarctic) Salix species occur in the British Isles, 25 hybrids involving these species are also known, all confined to Scotland. The latter figure includes crosses with one or more of the five otherwise ‘lowland’ willow species that can co-occur in the same mountain habitats.

A considerable overlap is also seen in the general appearance of different hybrid crosses having one parent in common. Several British willow hybrids involve three parent hybrids: these are termed tri-specific hybrids. Accordingly the montane willow hybrids are possibly the most difficult of all plants to identify THE ALPINE GARDENER

SALIX X BOYDII

Boyd believed that Salix reticulata, above, was a parent but there is much doubt

satisfactorily in Britain. This stricture clearly applies to S. x boydii.

Little progress in our knowledge of these plants has taken place since Victorian times, when there was considerable interest in them. In the early 1980s, a programme to re-assess them was undertaken (see Watsonia 25:65 (2004)), followed by a more scientifically based approach at the Royal Botanic Garden Edinburgh between 2002-05, using molecular techniques to study their DNA. Unfortunately S. x boydii was not included in this work.

DECEMBER 2015

Despite Boyd’s assertion, I have always doubted that Salix reticulata was one of the parents of S. x boydii. These doubts were shared by R. Desmond Meikle, onetime British willow expert and Botanical Society referee.

Early salicologists claimed to have discovered various other willows in Britain with hybrid combinations that involved S. reticulata. Only one of these, S. arbuscula x reticulata, is currently accepted. It looks nothing like S. x boydii. Hybrids between S. herbacea and S. lapponum or S. lanata were 455

SALIX X BOYDII usually responsible for these mistaken identities, for they produce hybrids which sometimes have orbicular, rugose leaves with reticulate veins, rather like those of S. x boydii.

So what exactly is S. x boydii? Linton suggested that one of its additional parents was likely to have been S. herbacea. This would certainly explain some of the characters that cannot be adduced to a simple cross between S. lapponum and S. reticulata. A Scandinavian salicologist, B. Floderus, suggested in 1932 (annotation on a herbarium sheet) that it is merely an anomalous variant of S. lapponum.

While this cannot be rejected out of hand, this theory fails to explain how some of the unique characters have arisen. It is more likely to be of hybrid origin. The orbicular, rugose leaves of S. x boydii superficially resemble those of S. reticulata, but such characters can also be witnessed in other British willow hybrids not involving this species, such as S. obtusifolia and hybrids with S. herbacea in their make-up, as mentioned above.

Characters that strongly contradict the involvement of S. reticulata include the thick, upright branches, the very short petioles, and the catkins, these having no resemblance whatsoever to this species, resembling instead those of S. lapponum. The characters of S. x boydii, except perhaps its growth habit, can be explained by the influence of several other willow species, namely S. lapponum, S. lanata, S. herbacea and possibly S. aurita. Yet the chance of a multi-parent hybrid occurring naturally in the wild and involving all these 456

species is very remote. Hybrids with three parents have been recorded in Britain; others with a large number of different parents have been synthesised in cultivation.

I have deliberately produced willow hybrids in this manner, attempting to recreate a plant like S. x boydii, mostly by using S. x obtusifolia crossed with S. x sadleri (S. lanata x herbacea) as the parents, since both these hybrids occur near Boyd’s find site. Some of the progeny from these synthesised crosses have affinities with S. x boydii but so far none have been close enough to offer conclusive proof.

Salix x boydii rightly remains one of the most popular dwarf shrubs grown by alpine enthusiasts, having an unmistakeable bonsai-like appearance, and fortunately it remains freely available in horticulture. It is also clearly very long-lived since one of Boyd’s original plants, still said to exist in his former garden, after more than 40 years had not exceeded a height of one metre (AGS Bulletin 1940, volume 8, page 28) and 25 years later was still under 1.4m tall (AGS Bulletin 1966, volume 34, page 274). This makes it suitable for almost any rock garden or even a trough. (Ray Drew reports that specimens continue to flourish in Anne Ashberry’s renowned troughs, now over 50 years old and moved long ago to The Forge Nurseries at Rawreth, Essex. Curiously she mentions several other dwarf willows but not this one in her influential 1967 book Gardens in Miniature.)

In conclusion, S. x boydii is thought to be a hybrid whose parentage has yet to be unravelled. It is, however, proposed THE ALPINE GARDENER

SALIX X BOYDII

The red seed pods of least willow, Salix herbacea, but is it a parent of S. x boydii?

that S. reticulata does not constitute one of its parents, as originally suggested by W.B. Boyd and given as fact in numerous publications.

One suggestion, that it is a unique variant of S. lapponum, cannot explain away several of its distinctive characters.

It might be a hybrid with three or more parent species, resulting from the further hybridisation of other known hybrids. As discussed earlier, three or even four species have all been suggested as potential parents, or in combination.

Attempts to recreate a plant that looks like S. x boydii by deliberate artificial crosses have met with some DECEMBER 2015

success but so far an exact match has not been achieved. Such experimental hybridisation should continue, although a more scientific approach will probably be necessary.

A chromosome count would prove little, given that the British montane willow species are all diploid (2n = 38) and that diploid forms of the ‘lowland’ species S. aurita very probably exist in Scotland. Molecular studies examining the DNA of S. x boydii will be especially tricky if it is indeed a multiple hybrid.

Yet this might be the only means of determining the true nature of Boyd’s remarkable willow.

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PLANTS FROM OUR SHOWS Cyclamen are undeniably, unfailingly the dazzling troupers that form the backbone of the autumn shows, so it is fitting that we feature two of them in this review of 2015’s four end-of-season events.

Where better to start than with C. hederifolium, present in virtually all its floral and foliar variations at the last gathering, held for the first time at RHS Harlow Carr? Here, as at the previous three events, two classes, in both the large and small Open Section, were devoted to the ‘group’ – the wording acknowledging that C. confusum and most recently C. crassifolium (the latter first described just over a century ago) are nowadays widely considered by aficionados as bona fide separate species.

The flowers overall vary relatively little in form (although their size is another matter, with the largest almost 4cm long, while their overwhelmingly demure, down-turned deportment is reversed in a freakish variant: ‘Stargazer’ gapes upwards, in ungainly fashion, as if throttled and turned on its head).

Of the more orthodox variants, Anne Vale’s f. albiflorum had barely come into leaf, but crammed a truly remarkable number of blooms into its tightlypacked 19cm pot. This was a chaste example, but some specialists get very pernickety indeed about even the faintest tinge of pink around the nose of the flower, as if this slightest of stains makes them inadmissible for inclusion under this subheading. Mid-through to dark purplish-pink permutations were also exhibited, none of them quite as floriferous.

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A Chilean charmer 2015 SHOWS FEATURED: Kent Autumn, Loughborough Autumn, Newcastle, Harlow Carr COMPILED FROM REPORTS BY: Don Peace, Eric Jarrett, Peter Hood and Robert Rolfe

Bog-standard Cyclamen hederifolium has perfectly pleasant but rather subdued foliage, ivy-like – despite the epithet – in only the wildest imaginings.

However, since the middle of the last century at least, extraordinary variations have been selected and fixed by linebreeding, from samplings made both in cultivation and in the wild, where the range can often be very diverse. One of the finest examples is that discrete collection of descendants presently conceived as Bowles’s Apollo Group, representing plants sired by a virtuoso seedling selected by Gerard Parker at Myddleton House (onetime garden of E.A. Bowles). In this, strictly speaking, the leaf blade has an extensive silver ground, divided by an elaborate green zoning and then whole typically pinkflushed, though this latter coloration sometimes fades away fairly early on.

Steve Walters staged a resplendent flagcarrier, with an abundance of mid-pink flowers attesting to its floral as well as its foliar excellence.

THE ALPINE GARDENER

FARRER MEDAL WINNERS 2015

JON EVANS

KENT AUTUMN Sternbergia sicula (Lee & Julie Martin) LOUGHBOROUGH AUTUMN Cyclamen maritimum (Ian Robertson) NEWCASTLE (SRGC Forrest Medal) Gaultheria ‘John Saxton’ (Keith & Rachel Lever) HARLOW CARR Cyclamen colchicum (Dave Riley)

Leucocoryne odorata shown by Bob and Rannveig Wallis at the Wimborne Show this year

Other variations have especially deeply lobed leaves, or conversely they can be more or less entire, either narrow or very broad, and in some there is no patterning whatsoever, the entire surface being silvered or pewter-tinged, as with ‘Nettleton Silver’ and ‘White Cloud’. A few take on seemingly artificial, house plant-like guises: the same exhibitor showed perhaps the most extreme of DECEMBER 2015

these, ‘Tilebarn Shirley’, whose narrowly ovate leaves have a creamy-white central blaze and a broad, darkish green margin, the almost waxy, large and pure white flowers hovering on sturdy stems.

The season’s last hurrah Almost 20 years ago, when this rare Caucasian endemic was first 459

PLANTS FROM OUR SHOWS shown to the Joint Rock Garden Plant Committee by RBG Kew, Michael Upward proclaimed that the name Cyclamen colchicum was nonsensical.

Versed in both Latin and Russian, he was being typically mischievous, for he was perfectly well aware that the specific epithet derived from Colchis, a classical region of onetime Asia Minor to the east of the Black Sea. In print, of course, it looks like the name of one genus piled incongruously upon that of another, as also with (for example) Campanula saxifraga (from the same range of mountains) and NW American Senecio soldanella. These coinings are all legitimate, if a little unusual and seemingly oxymoronic.

Cyclamen colchicum remains uncommon in gardens (and in the wild, where it is presently only known from its type locality in Abkhazia, and since 2010 from another localised population in western Georgia). But now it is offered by at least one specialist nursery and appears in a small number of seed lists. Cross-pollination is recommended where two or more plants are to hand, since it can otherwise remain resolutely barren year after year. Such had been the case with Mike & Christine Brown’s plant, handed to its present owner, Dave Riley, almost on a whim, after Christine had meticulously removed the spent flowers one and all, unaware that her husband had painstakingly been at work with an artist’s paintbrush, determined to engineer a seed set.

By that time the corm was around ten years old: it has subsequently been repotted several times (in early autumn), 458

the compost heavily laced with leafmould but well-drained. Surprising that the clay pan selected was so shallow, when one thinks of the full (i.e. deep) pot routinely used to accommodate C. graecum and C. hederifolium. That said, it typically tucks itself into steep limestone cliff crevices, and as such is accustomed to root restriction. The altitude range is from 300-1,400m and its hardiness doesn’t appear to be problematic, under cold glass protection.

Even so it is very unusual indeed to see it planted outdoors. The flowering period is given as June-October, but in cultivation in can flower as early as June, sometimes even before the first of the new leaves (it is almost evergreen but will defoliate if kept dryish in the summer), alongside last year’s only just ripened seed capsules.

It is most closely related to southcentral European C. purpurascens (which has alternatively been christened C. europaeum, with its disjunct, Russian relative given as var./subsp. ponticum).

Differing in its thicker, regularly and palish-peripheral-pimple-edged leaves, these are typically patterned silvery-grey towards the margin in a quietly attractive fashion but are occasionally plain green, as with the selection ‘Deirdre’, to date the only cultivar widely canvassed.

The flowers are often ighly fragrant, a character very apparent in the confines of a warm greenhouse, and up to 22mm long, the petals more pronouncedly twisted longitudinally in the plant shown than in others, where they can be only half the size and given as ‘dumpy’.

THE ALPINE GARDENER

JON EVANS

Leucocoryne odorata shown by Bob and Rannveig Wallis at the Wimborne Show this year

An albino example has apparently not been recorded, but as with almost all other species, it is surely only a matter of time before one crops up.

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Full show reports and more pictures can be seen on the AGS website

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ULSTER SHOW

Pictures: Heather Smith

Gentiana acaulis (Paddy Smith) The very good pans of spring and trumpet gentians on show were mostly grown by the same man, who had raised the lot from seed.

This handsome clump won him the Farrer Medal. The compost – neutral heavy loam from his garden, leaf-mould and grit, with a spicing of Vitax Q4 fertiliser – clearly works wonders.

Cassiope ‘Askival Snowbird’ (Cilla Dodd) Thirty years ago Mike and Polly Stone raised hybrid cassiopes that had C. wardii and C. selaginoides as the seed parents. The pollen parent could often be deduced by the habit of the seedlings. Those considered as C. selaginoides x mertensiana were named the Snowbird Group, referring to all those that conformed.

‘Askival Snowbird’ is a selected individual.

Cystopteris dickieana (Don Peace) British native ferns were well shown throughout the season and this one (which only just qualifies under this heading on the basis of a toehold in Scotland) made repeat appearances, garnering a Certificate of Merit on its Irish trip. Now 15 years old, it had germinated by chance in Don’s alpine house sand plunge.

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THE ALPINE GARDENER

LONDON SHOW

Pictures: Doug Joyce

Iris lacustris (Tim Lever) The spreading stolons of this Great Lakes miniature form a tangled mat just below the soil surface, so it is seldom grown in a pot, other than to establish divisions before planting these out in moist but well-drained parts of the garden. Its fleeting flowers put on a fine display and it was adjudged best plant from North America.

Fritillaria assyriaca subsp. melananthera (Peter Furneaux) Several Turkish and Iranian species conform to the template of a narrow and slightly curvaceous flower, alternatingly striped jade and black. Their taxonomy remains in flux but this plant, known from a few low-altitude populations in south-central Turkey, has settled down well, though this abundant, astonishing potful has surely never been bettered.

Asperula arcadiensis (Martin & Anna-Liisa Sheader) Sometimes seen in untidy, sprawling condition, this narrow Peloponnese endemic benefits from a determined haircut after it finishes flowering.

Outdoors, a vertical crevice in a tufa block is recommended. The exhibited plant had been subjected to a different form of root restriction, for it was unconventionally housed in a shallow terracotta pan, inducing it to form a tight, low mat, plastered with softest pink, long-tubed flowers.

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EAST ANGLIA SHOW

Pictures: Doug Joyce

Haberlea ferdinandicoburgii (Peter Farkasch) His second Farrer Medal plant this year, Peter Farkasch’s Haberlea drew plaudits for its floriferousness and compact nature, along with its pristine foliage. This Greek/Bulgarian gesneriad, generally found in limestone gorges, sink holes and ravines, is often treated as a synonym of H. rhodopensis but is the subject of ongoing study at RBG Edinburgh.

Draba longisiliqua (Martin Rogerson) This Certificate of Merit specimen reached its peak a month later than one would expect. First introduced by Martyn Rix in 1982, seed has been sent back from the Caucasus perhaps just once since. Its greyish-white foliage is arguably more attractive than any other species, its flowers larger than any of its close allies.

Delosperma ecklonis ‘Fire Spinner’ (Audrey Dart) Knowledge concerning the genus proceeds apace.

Many are inter-fertile and hybridise in gardens, but this richly coloured novelty was introduced from near Tarkastad in the Eastern Cape by Panayoti Kelaidis, who found it at around 2,000m. It is both hardy and deer-proof!

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THE ALPINE GARDENER

MALVERN SHOW

Pictures: Jon Evans

Petunia patagonica (John Kemp) At one time it was thought impossible to flower this plant in cultivation. Like the Leucocoryne prefacing this review, it salutes John and Anita Watson’s endeavours (F&W 9290): they sourced seed from Argentina’s Santa Cruz steppe 15 years ago. Surely the best seen to date, this was a very densely flowered specimen. Kept in a briskly ventilated alpine house, it occupies a sand plunge and requires a very gritty, sparse compost.

Primula halleri (Sonia Morris) With flowers twice the size of more familiar allied species such as P. frondosa from Bulgaria (where it is also native, though only in the Rila and Pirin Mountains), this too littleseen Section Aleuritia (Farinosae) species is found mainly in the central and eastern Alps. This clump at its peak received the Susan Clements Trophy for best plant in the Intermediate and Novice Sections. It had been grown in semi-shade in a humus-rich, well-drained compost.

Dionysia involucrata ‘Gothenburg White’ (Paul & Gill Ranson) This late-flowering species lasts longer than any other and appeared here a fortnight after its London excursion, in even better condition. Albino examples of the genus were first reported for Iranian D. curviflora but are even now rarely grown. Henrik Zetterlund was instrumental in spreading this true-breeding novelty, which has happily persisted.

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SOUTHPORT SHOW

Pictures: Don Peace

Fritillaria camschatcensis (Clare Oates) The Farrer Medal was won here for the second year running by Clare Oates, last year with a mature Lewisia ‘George Henley’, this time round with a large pot of Fritillaria camtschatcensis.

Coming at the very tail-end of the flowering period for this much-exhibited genus (the majority bloom during March and April), it exudes a stench to attract pollinators.

Eriogonum umbellatum var. haussknechtii (Trevor Whitaker) This distinguished North American was awarded a Certificate of Merit. It forms mats up to 60cm across, the bright yellow inflorescences held on stems 2-7cm long.

A scree-dweller from the treeline and above (to around 2,100m), it has been offered in Ron Ratko’s Northwest Native Seed lists.

Androsace wardii (Frank & Barbara Hoyle) From south-west China and adjacent Tibet, this rarely exhibited species had never flowered until now. Frank said that in winter it looks ‘like a brown ball’ and ‘as it starts into growth, it produces small green shoots that then look as if they are going to die’. Grown in an ‘alpine’ mix of 50/50 John Innes No. 2 and grit with the addition of brackenmould, it is a magnet for greenfly.

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THE ALPINE GARDENER

WIMBORNE SHOW

Pictures: Jon Evans

Lewisia rediviva (Martin Rogerson) A six-pan, AGS Medal entry was spearheaded by this notable white through to deep pink, deciduous species, best left unwatered in summer and indeed well into autumn. Some forms are reluctant to multiply their crowns. Others steadily increase and after ten years or more can issue a mass of buds that in good light will open and entrance for a day or two.

Globularia bellidifolia (Ian Sharpe) In the Pyrenees and the Alps these mat-forming plants are typically plastered with short-stemmed, globular, blue flowers. Their taxonomy is rather involved, and this species is often referred to as G. meridionalis, with several clones selected in recent years. Seen at their best in a trough, spilling over the edge of a raised bed or in a crevice garden, they flower in British gardens in late April or May. Pleione chunii (Ian Robertson) Several fine orchids were present. Diane Clement’s pot of Cypripedium cordigerum was particularly impressive.

Of the others, demure Pleione chunii, grown in pure Sphagnum moss

by Ian Robertson, was outstanding. This epiphyte from a scattering of Chinese provinces is among the last of all to flower.

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BAKEWELL SHOW

Pictures: Robert Rolfe

Edraianthus dinaricus (John & Clare Dower) There are several very similar cushion Edraianthus, difficult to tell apart when, as in the case of this plant, they are covered in flower, cloaking the distinguishing foliar characteristics. This was a dazzling example, fully 20cm across, with every one of the several hundred purple flowers in its prime.

Aquilegia ottonis subsp. amaliae (Lionel Clarkson) This dwarf Greek columbine is less susceptible to hybridisation under garden conditions than many of its brethren, and can be thoroughly recommended.

The bicoloured flowers are produced on stems to 30cm tall (rather less if grown outdoors) and gentle self-seeding can be expected.

Rhododendron calostrotum subsp. keleticum (Norman Davies) This floriferous dwarf was one of several accomplished entries from Norman Davies, who won the Charles Graham Trophy for best plant in the Intermediate Section.

It’s an easy and long-lived plant in the garden that can grow to a metre across in ten years if given the neutral to acid, peat-rich soil it craves. Cuttings take readily and you may be able to detach rooted pieces from an established plant.

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THE ALPINE GARDENER

PERSHORE SHOW

Pictures: Doug Joyce

Campanula fragilis (Edward Spencer) One anticipates a good range of campanulas at this show and they were present in quantity.

In the heat of the glasshouse venue, some needed last-minute dead-heading. This abundantly flowered mound earned the exhibitor a first Farrer Medal.

The dome hadn’t succumbed to the downfall of many cultivated specimens, which are splayed due to the weight of their display.

Allium paniculatum (Lee & Julie Martin) Obtained as Californian Allium serra, this was not that species (a serpentine endemic from the Coast Ranges with bright pink flowers) but rather a form of the European/ Asian A. paniculatum (naturalised further afield, California included).

Some 20cm tall and with cascades of pale pinkish-brown flowers, it was immaculate: Lee had spent hours removing the dying foliage.

Spigelia marilandica (Joy Bishop) This plant, grown from seed, is from the south-eastern United States in the main, across to eastern Texas, and ironically now rare in its nominate state of Maryland.

Selected clones are now sold under names such as ‘Red Feather’ and ‘Wisley Jester’. This striking species can attain a height of 60cm but as seen was barely half as tall.

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ISSN 1475-0449