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JOHN NEGUS

John will reply personally to all your gardening questions

Merendera montana is a native of the Central Pyrenees

W i k i m e d i a Fuchsia gall mites cause plant distortion and are spreading from the south

How do I deal with fuchsia gall mite?

QIn my mum’s garden she has a large number of fuchsias. They are beautiful when in flower but seem to have all got this gall mite. Is there any way of saving them, maybe by cutting out the infection? Some are 20 years old.

Sue Read, Brighton

AThe fuchsia gall mite is a serious pest of fuchsias. It is rare, but has All you can do is cut off and dispose of the infested shoot tips – never add them become more widespread since they first arrived in 2007, particularly in the south of the UK.

The mites are microscopic and suck the sap at the fuchsia’s shoot tip, secreting chemicals that cause the plant material it to become distorted. The greater the infestation, the greater the distortion, until the plant is incapable of producing normal-looking leaves.

Unfortunately there are no chemical treatments that work on the gall mites they are immune to all known products. to the compost. Predatory mites can be bought as a biological control, but suppliers say you need to reduce the affected shoots to 4in (10cm) below affected growth before introducing the predator. This biological control can be bought online from nematodesdirect.co.uk, 0808 901 2055. Some fuchsia cultivars are said to be more resistant to the mites, including ‘Baby Chang’ , ‘Cinnabarina’ , ‘Miniature Jewels’ and ‘Space Shuttle’ .

Unknown beauty

QCan you name this plant for us? Gill Smithers (via email)

AThe interloper appears to be Merendera montana, a native of the Central Pyrenees and Iberian Peninsular. Relatively hardy in sheltered gardens, its ribbon-petalled flowers have great appeal. Indeed, it makes a fetching contender for a sunny rock garden. It normally flowers in autumn, but prolonged spells of hot weather will trigger an earlier blooming.

It develops from a corm which, if nourished monthly with fish, blood and bone meal, will probably multiply to give you more flowers next year.

Blossom end rot is caused by irregular watering

What is the name of this cheerful yellow plant?

QPlease can you identify this plant? Is it some sort of goldenrod?

Suzanne Shaw (via email)

AThe plant in question is hardy yellow loosestrife (Lysimachia vulgaris). Splendid for cheering summer, but it can be invasive.

Another, equally appealing form called L. congestiflora ‘Outback Sunset’ , is a splendid summer-bedding contender, magnificent when cascading from a hanging basket.

It must be Yellow loosestrife blaze of yellow brings to the a overwintered summer garden in a warm greenhouse or on a sunny windowsill.

If you wish to propagate L. vulgaris, divide the clump in autumn and replant chunky well-rooted divisions. Dead-head regularly to encourage more blooms.

Tomato disaster

QCan you please advise me as to what is wrong with my ‘Money Maker’ tomato plants?.

Lynda Grace (via email)

AYour tomato fruits have succumbed to a disorder called blossom-end rot, triggered by an erratic uptake of water. If you water regularly to keep the compost or soil nicely damp, further fruits will develop normally.

Additionally, feed twice-weekly with a high-potash liquid feed, but never liquidfertilise dry soil.

Fairy ring fungi can be tricky to remove

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JOHN NEGUS

John will reply personally to all your gardening questions

Quick questions & answers

I’m not at all enchanted by these fairies!

QI have a brown semi-circle on my lawn which has some fungi in it and there is also a patch of fungi in the border. Do you have any idea what it is or how I can get rid of it?

Agnes Nash (via email)

AThese half circles of toadstools are known as fairy rings or pixie rings, However, there are some things that you can do to reduce the impact of the caused by a fungus which feeds on the roots of grass causing browning.

There may be lush green growth adjacent to the brown arcs or circles. The fungi is hidden below ground for most of the year, with the fungi appearing in late summer/autumn.

Unfortunately it is very difficult to eradicate fairy rings and there are no chemical methods available. A permanent solution involves removing infected soil and replacing it with new topsoil and then reseeding or returfing, but this has no guarantee of eradication. fairy rings. Firstly, remove toadstools as soon as they appear to reduce the spread of spores. Secondly, reduce the amount of organic matter available to the fungus by always collecting up the grass mowings and by raking or scarifying in early September. Thirdly, spiking helps to break through the water repellent fungal mycelium in the soil, which helps to prevent the grass from drying out. Finally, keep lawns watered in dry weather and well fed to even out the colour of the grass. Rake out dead areas, spike and reseed. Q What is this plant?

QWhat is this plant?

Helen Field (via email)

AIt is commonly known as Angel’s Fishing Rod (Dierama pulcherrima).

This is a member of the iris family, native to South Africa but quite at home in Britain.

It is easy to grow in any ordinary garden soil, ideally in sun but it will tolerate partial shade.

Margaret Balfour (via email)

AThe shrub is Deutzia scabra ‘Candidissima’ , a double white form of the parent, D. scabra. Prune after flowering and feed monthly, April to September, with a general fertiliser and with bone meal in October.

How do I care for indoor cyclamen?

QI managed to salvage my cyclamen that had dried out in the conservatory. How do I care for it now?

Barbara Trevitt, Newcastle upon Tyne

AThank you for the attached image of your lovely cyclamen. We are and continue delighted that you rescued it and it is now fully recovered and about to flower.

Encourage it to excel by liquidfeeding it twice weekly with a highpotash tomato feed.

Hopefully, it will continue blooming throughout winter and into next spring.

When blooms fade, gently twist flowered stems from the tuber.

Ideally, in late May when frosts finish, move it outdoors to a lightly shaded spot watering and feeding Indoor cyclamen it until its leaves shrivel naturally die back after flowering and die and can be removed. Then do nothing until little pink buds, the leaf initials, appear on the tuber. That’s your cue to re-pot it in a slightly larger container using ericaceous compost. Bring it indoors in late August.

F u t u r e Q I have little white flies on the plants in my hanging baskets. What should I do?

Jan Schut (via email)

AThe white creatures are sapfeeding whiteflies.

I suggest that you spray your plants with Bug Clear Ultra, a systemic preparation that protects plants from attack for around three weeks.

Contact John Negus by email address below Email: amateurgardening@futurenet.com

Tradescantia fluminensis likes a warm, well-lit room

Black spot on many plants can be tackled with good husbandry and carefully administered fungicide spray

Can rose black spot affect other plants?

QI’ve always had to spray an old rose carefully for black spot. I’ve noticed that a nearby honeysuckle and also a hydrangea are affected. Is this the same variety of black spot?

Alison Ireland, Kirn, Argyll

AI am sorry that your roses have succumbed to black spot disease. Additionally, feed your bushes with 1oz (28g) per sq m of sulphate of potash. The best way to control it is to spray with RoseClear Ultra Gun, which also very effectively tackles powdery mildew, rust and aphids, or FungusClear Ultra Gun that protects plants for over four months.

Alternatively, use Bayer Garden Fungus Fighter Plus that guards roses from attack for up to three weeks. Sprinkle it over the root area, monthly, from April to September, and water it in. Your hydrangea and honeysuckle are affected by another fungus, not black spot which is specific to roses. Treat plants with FungusClear Ultra Gun and feed them with sulphate of potash, which will strengthen them.

What do I do about ground elder?

QPlease can you tell me if this is ground elder.? I have it all over my garden and nothing gets rid of it. The more I dig all my beds over, the more it pops up!

Mrs M Hawker (via email)

ARegrettably, the invader in question is indeed ground elder.

Best tackled by painting or very carefully spraying its leaves with a glyphosate-based weedkiller, it will eventually die.

Weedkiller treatment is better than hoeing it out, which breaks roots which then regrow.

Another option, if the situation is appropriate, is to cover the interloper with weed-proof membrane: no light means no growth.

Camouflage the membrane by sprinkling it with proprietary composted manure or similar crumbly organic material. Q Please could you identify this pretty climbing plant that I got a cutting of when on holidays in Salou?

Ground elder is a common menace

Wandering joy

Pauline Gaffney (via email)

AThe cascading/climbing plant is wandering Jew (Tradescantia fluminensis). A native of Brazil and Argentina, it sports small white flowers in leaf axils.

Ideal for growing in a well-lit, warm room where it has space to cascade and please you with its foliage, it needs very little attention, apart from regular watering and occasional liquid feeding.

It is easy to propagate from cuttings rooted in water or gritty soil.

QThis has popped up in my garden. What is it?

Mystery appearance

Mayo Marriott (via email)

AIt is a plume poppy (Macleaya cordata also called Bocconia cordata). A native of mountain woodland in eastern China Plume poppies are a tall and Japan, its and beautiful addition impressive heads of feathery, creamy-white blooms are best in June and July.

Normally growing from 5-8ft (1.52.4m), it thrives in most enriched soils. It enjoys full sun and is easily propagated from rooted suckers.

Ask

JOHN NEGUS

John will reply personally to all your gardening questions

Will I be able to save my hydrangea?

QI have a hydrangea in a tall pot wide at top and narrow at the bottom, but it looks as if it is dying off. I have re-potted it in new soil, will it come back again?

Irene Collins (via email)

AI am sorry that your hydrangea is wilting. Are you watering regularly? This shrub is a moisture lover and it’s vital to keep the compost damp.

If you are watering frequently and the plant is still flagging, then something could be damaging the roots and preventing them from absorbing water.

It’s probable that vine weevil grubs – tiny dirty white curved creatures – are feeding on the roots, which I urge you to examine. If it’s a large pot, it may be a two-person exercise removing the root ball carefully, trying not to damage it.

If you spot grubs, replace the root ball and water it with Bug Clear Ultra Vine Weevil Killer, which destroys grubs and protects plants from further attacks for two months.

If no grubs are found, then your pot

Hydrangeas thrive in pots unless they are too dry or attacked by pests

soil could be too dry and your hydrangea is short of water. It should respond quickly if you water it well.

Alternatively, the compost may be too wet and air is being driven out, which would cause the plant to suffer.

Ideally, if you are not already doing so, sit the pot on ‘feet’ so that surplus moisture freely drains away.

Feed and water gerberas to keep them flowering

Myailing gerberas

A wild discovery

QI planted three hardy gerberas in April. All started to wilt, then two came back well but the third remains very sad. What can I do?

Lesley Gibbard (via email)

AAt this time of year, gerberas should be flourishing and flowering profusely. I suggest that you encourage them to perform better and grow well by liquid-feeding them weekly with a highpotash tomato fertiliser.

Water the soil copiously before feeding. Then, in late autumn, mulch them thickly with composted manure to insulate roots from frost.

Prickly lettuce is an uncommon wild flower

Clematis viticella ‘Alba Luxurians’ can flower in different colours

Is my Clematis viticella an anomaly?

QI bought a clematis viticella ‘Alba Luxurians’ from an RHS garden and it’s been wonderful – white flowers tipped with green. I ordered another one from a nursery and the flowers came up light mauve one year and white the next. Is this normal or is mine behaving strangely?

Joan Barton (via email)

AClematis viticella ‘Alba Luxurians’ is not a stable variety and blooms which are normally white with green tips and flecks can occasionally be tinged with mauve or violet.

If it’s cold when flowers are opening, they tend to be more green than white.

The fact that in its first year blooms were pale mauve, then, in its second season were white, indicates that it is not your soil that triggered a change of colour but the plant’s unstable and variable genetic constitution.

I have this variety cascading from a wall and illuminating wonderfully a gloomy part of the garden. Q Could you tell me please what this plant is called?

Helen Symonds, Little Melton, Norwich.

AIt is prickly lettuce (Lactuca serriola). A tall and statuesque annual British wild flower, it blooms from July to September and often appears in large groups –‘reaching for the sky’ .

I haven’t seen it for some years. If it’s in your garden, I urge you to gather ripe seeds and sow them in a sunny spot where plants can naturalise and attract a wide range of insects. Without doubt, it has character.