Read URSULA BUCHAN’s Spectator article in the Green Room. Does the increase in global warming mean British gardens will change? And how?

Time was when golden mimosa was an exotic plant you bought in a florist in January, or admired on a winter holiday in the South of France or Cornwall. No longer. The little puffy balls of yellow flowers are moving north and east. The Mimosa Meter registers Acacia dealbata in London and in sheltered gardens all the way up to north Humberside. Since it will tolerate a few degrees of frost for short periods, it might be worth planting now anywhere in the lowlands of England and Wales, That is, if this past winter is part of a pattern, as the scientists tells us it is, rather than an aberration.

Changing climate, we are told, means stronger winds, particularly in autumn and spring, together with wet, mild winters that produce only the odd, short-lived episode of snow and no sustained periods of freezing weather, less incidence of spring frosts and then long, hot, dry summers. What happens, in these changed circumstances, to existing gardens and plantings, based very largely on reliably frost-hardy trees shrubs herbaceous perennials and bulbs; the kind of garden for which we are particularly known across the world?

It seems to me that there are a number of relatively easy things we can do to mitigate the worst effects of climate change on them. We should plant everything small, especially trees, so that they are well-anchored by an extensive root system in the soil and able to withstand gales. We should lighten heavy soils with grit and bark chippings, so that plant roots aren’t sitting in sopping soil through the winter.

For those plants which need moisture in summer such as South African bulbs, we should mulch the soil heftily in spring, so that it stays moist despite a beating sun in July; in the case of frost-tender plants, the mulching should be done in the autumn to prevent the roots from freezing. We should plant shelter beds, and, if that interferes with the view, then internal shelters using hedging plants. Northern European perennials and blackcurrants, which need substantial winter chilling, should be plants in the coldest part of the garden if possible.

You may wonder whether it is worth that bother to maintain our hold on traditional types of garden making, using well-tried plants with which we’ve become comfortable. The alternative, however is to risk a mish-mash of conflicting styles. Just because we can get something to grow doesn’t mean we have to. I shall refrain from planting a mimosa yet awhile.

Reproduced with the kind permission of The Spectator from “The Climes They Are A-Changing” by Ursula Buchan, as featured in The Spectator Guide to Gardening, supplement, 28.iv.07