A DROUGHT SURVIVAL PLAN

In Australia, the next drought is inevitable. Yet all around me I hear, ‘when the seasons return to normal’ and ‘now that the drought is over’. It’s as if we refuse to recognise the nature of our land. But we must consider the way we garden, the way we farm and the plant choices we make to survive with these droughts, not in spite of them.

Words Carolyn Robinson Photography Claire Takacs, Annabelle Hickson

I have gardened through severe droughts before. Between 1991 and 1995, 2000, 2002 and 2009, with prolonged dry spells in between. But this most recent three-year drought, particularly last year, was off the charts. Especially the extraordinary heat, which made everything worse.

Soil, plant and atmospheric moisture was stripped away and we watched as the tree canopies in our gardens and native bushlands around us fried in the daily heat.

The worst aspect of droughts is how interminable they seem. The dry bare soils, the dust and then the smoke. Day after day after day. And then one day it rains.

When we moved to Eagles’ Bluff, a property in a quiet valley south of the New South Wales town of Tenterfield, I was well aware that my water supply was limited. Our small river did not run permanently and our soils were not conducive to holding water in dams. I do believe dams can be useful, but unless they are monstrous in size or spring fed, they are of limited help in a severe drought. My father always said that when you need your dams the most, they are dry. So instead we invested in two 250,000 litre tanks, not ever thinking that for almost a year my 2.5 hectare garden would, or in fact could, survive largely intact with a handheld hose.

In retrospect, I have realised that there were several factors that assisted in that survival.

PREPARATION When I create a new garden bed, I incorporate large quantities of organic matter, which greatly increases the moisture-holding capacity of the soil. I also rip the soil deeply. This enables plant roots to push far down into the soil in their early life. I then protect the beds and new plants with rock mulches.

On the subject of mulches, many people think that mulching heavily with organic mulches such as lucerne will protect their gardens from drought. But if the mulches are too thick, the small amounts of rain that do fall during a drought do not get through to the soil underneath. I used organic mulch very sparingly during the drought period so as to maximise the penetration of our rainfall. After all, I certainly didn’t have to worry about weeds.

PLANT KNOWLEDGE Another key to the garden’s survival was my doggedness with the hose. I had a written schedule and hand-watered the gardens systematically. Although not all plants received a drink. Those that I knew (or hoped) were tough enough had to manage on the small amount of rain we received. I have gleaned more knowledge on plant drought-hardiness and resilience in the past two years than I had in the previous 10!

A couple of other things became clear, too. The plants that were the real survivors were also the biggest bullies: eucalyptus species, Chinese elms, gleditsia, ceanothus, acacias and melaleucas, to name a few. The other plants surrounding these bullies had a real battle to garner any water, but I did make an effort to keep the understory alive, as I realised that replanting would be very difficult. What new planting could ever compete with such tactics?

To my surprise, the native species did not outperform my drought-hardy exotics. I had significant native losses, especially with more short-lived species such as grevilleas. It stands to reason that a plant nearing the end of its life would not fight to survive, especially if a plant is a reseeder not a resprouter. (This latter, with the ability to resprout from the hardwood following times of stress, is very much overlooked by gardeners. Removing a large, dead grevillea and replanting with a new one is much more difficult than watching your callistemons reshoot from their own hardwood. That being said, I would not ever forgo my grevilleas: the habitat they provide for birds is fantastic.)

On the whole, I found that my deciduous or herbaceous species dealt with the prolonged drought better than many evergreens.

Many deciduous trees did not break their dormancy until almost the end of spring, after the good fall of rain at the beginning of November. It meant that these species needed very little moisture for six months; a huge benefit, especially when it came to my hand-watering efforts.

Evergreens, on the other hand, draw on soil moisture all year round. I should mention here, too, that frost exacerbates the effect of drought by dehydrating evergreen foliage further. Frosts are always harder in drought years when humidity and rainfall are low.

Despite the severity of the drought and its impact on our garden, the wider landscape had it worse. And so the garden became a haven for wildlife, with many birds, insects—particularly bees—reptiles and marsupials seeking refuge.

The garden pickings, however, were still very lean. The snakes I saw were very thin. Echidnas, who ordinarily hunt at night, were also busy during the day. They had a tough time digging for ants because the soil was so hard. Nevertheless, the garden provided more than was available outside.

WHAT LIVES OR DIES There comes a time when you must decide which plants your can save with your limited water. My strategy was to let the reseeders go. Plants like gaura and centranthus will reward you aplenty with lots of babies following rain. Bulbous plants such as dahlias, and those with fleshy roots such as tradescantia and hellebores, will retreat underground and then resprout when it rains.

With perennial plants that propagate through division, save one and let the others go. Last year when I was worried my water would not last, I built a holding bed and transplanted one of each of the plants I did not want to lose.

Concentrate instead on saving structural shrubs, trees and plants under the trees. Hedges too, although I found them difficult to water. I vowed that next time I plant a hedge, I’ll make sure it’s a resprouting species and I’ll plant it in a shallow trench so it can be flood irrigated.

Conifers, as a group, handled the drought poorly, with many losses; they don’t reshoot from the hardwood (an exception is English yew: Taxus baccata). A hedge with dead plants is a smile with a tooth missing.

Despite some losses, I am astonished at the survivability of so many species. It’s almost as if they metaphorically pulled in their belts, hunkered down, suspended growth or, in some cases, retreated underground and waited it out.

The water I was able to give to plants was limited: no more than a bucket each week. The soils became so dry that I dug a hole with a mattock around or uphill of the plants to help water penetration. It kept them alive, just.

I experimented with pruning, lifting tree canopies and cutting shrubs back, but decided from observation that the rule of thumb is to wait to prune back only following good rain. Pruning encourages a plant to want to grow which, if soils are dry, will only increase their stress.

There is no doubt that plant roots are compromised in drought and there is often significant dieback. Cutting back shrubs and perennials following good rain will facilitate their recovery.

IGNORE THE LAWN The drought was so severe and went on for so long that I thought that my lawn and grass areas could not possibly recover. They looked completely dead and in many areas there was just bare soil. Yet, a month after the resumption of good rain, the grass responded miraculously. The message here—particularly if you have running grasses such as kikuyu, buffalo, and couch—is not to waste precious water on lawns. They will recover.

To look on the bright side, there are gardening upsides to a drought: for almost a year I didn’t get out the mower and the weeds certainly kept their heads down.

I am so glad that I did not give up, although on so many occasions I nearly did. Talking to gardening friends helped; a misery shared was, to some extent, a misery halved or at least mitigated.

Over the past few years our land and gardens have endured floods, droughts and fires. The rain has come again and the gardens and hills are green. I think now is the time for us to hunker down, accept that droughts are part of life, and have a long think about what is happening to our precious planet. n

CAROLYN’S LIST OF DROUGHT-HARDY PLANTS

REQUIRED VERY LITTLE ADDITIONAL WATER trees and shrubs Abelia species Acacia species Acca sellowiana (feijoa) Arbutus x andrachnoides Atriplex nummularia Berberis species (can be heat affected) Buxus mycrophylla var. japonica Callistemon species Ceanothus x delileanus

‘Gloire de Versailles’ (where no tree competition) Coleonema pulchellum (dwarf) Cotinus coggygria Cytisus species Eleagnus ebbingei (if no tree competition) Eremophila species Eucalyptus species Euonymus japonicus Euonymus ‘Silver Queen’ Grevillea (shrubby varieties) Jasminum nudiflorum Lavandula angustifolia Magnolia grandiflora ‘Little Gem’ Mahonia bealei Nerium oleander Phlomis species and cultivars Prunus glandulosa ‘Rosea Plena’ Prunus laurocerasus and lusitanica Punica granatum (dwarf) Raphiolepis species Rosmarinus officinalis Senecio viravira Spiraea cantoniensis ‘Flora Plena’ Symphoricarpos albus Teucrium fruticans Ulmus parvifolia ‘Seiju’ Viburnum tinus perennials, small shrubs, ground covers and ornamental grasses Agapanthus varieties Allium species Amsonia tabernaemontana Artemisia species Ballota pseudodictamnus Beschorneria species Calamagrostis species Canna cultivars Dahlia varieties Euphorbia species Gazania species Helichrysum petiolare Iris tectorum Liriope species Lomandra species Miscanthus species Nepeta species Oreganum species Panicum species Pennisetum cultivars Perovskia atriplicifolia Poa species and cultivars Ruta graveolens Salvia (some species and cultivars) Santolina chamaecyparissus Sedum species Stipa species Tulbaghia violacea

‘John May Special’ Tradescantia species Yucca species MINIMAL WATER NEEDED

(less than 10 litres per week) shrubs Anisodontea hypomandarum Buddleia species Caryopteris cultivars Ceanothus ‘Marie Simon’ Choisya ternata Cistus species Correa alba Cotoneaster dammeri and horizontalis Daphne odora Deutzia gracilis ‘Nikko’ Euonymus alatus Homoranthus species Ilex species (holly) Kunzea species Lagerstroemia species Loropetalum chinense Philadelphus species Roses Westringia species

perennials, small shrubs and ground covers Achillea cultivars Agastachys species Aqueligia Bergenia species Boltonia asteroides Crambe maritima Dianthus species Echinacea Echinops ritro Epimedium species Erigeron Hellebores Knautia macedonica Melianthus major Polygonatum species Salvia species and cultivars