Even soaring temperatures seem a distant memory as the weather settles into a more normal routine. However, lengthy periods of low rainfall both in the summer and over the winter continue to take a toll on our landscape. The effects of drought may take some time to show in mature and veteran trees, but in newly planted trees the effects are striking, and if the longer-term picture is one of regular drought what can we do?
I have referred previously to planning and designing our gardens so as provide as much colour throughout the year as possible. Add to this the need to future proof our gardens against extended periods of dryness and we can avoid work and the loss of expensive plants.
As long ago as 1978 Beth Chatto published her now famous book ‘The Dry Garden’ inspired to some extent by the establishment of her new garden on wasteland in an area of low annual rainfall. The Gravel Garden she created in Colchester happens to be in the driest area of England and it inspired a new type of gardening. She wrote that ‘This garden was not to be irrigated in times of drought. Once established, the plants must fend for themselves or die’.
Now forty-four years on Beth Chatto’s work has become crucial to the way we need to think about gardening. Since then, many horticultural organisations have written on the subject including the RHS who have come up with a list of their top five drought resistant plants. This is very useful so here they are:
Abelia x grandiflora
Euphorbia characias subsp. Wulfenii
My top tree list would include Acacia dealbata (mimosa), Cercis siliquastrum (Judas tree), Koelreuteria paniculate (golden rain tree). There are a few shrubs I have used in dry areas too and these include most of the Hebes, Lavender and Artemisia ‘Powis Castle’, Halimium, and Nandina domestica which is the sacred bamboo. There are many perennials too and I would definitely recommend Euphorbias, Echinops, and Heuchera.
More generally it is possible to recognise plants in terms of their drought resistance whenever you are in a garden centre. Look for plants with either silver or grey green leaves. Leaves that are light in colour tend to reflect light whilst those with fine hairs help to trap moisture around plant tissues.
When establishing plants think about the best time to do this. With trees and shrubs there is a definite planting season between October and March. If you plant within these months then the shock of disturbance is less, allowing the plant to become properly established with a good root system. This is particularly true for trees. There is a strong case for planting smaller, less mature trees that will have a large root system compared to their canopy and leaf surface. This will enable it to establish more quickly than a mature tree.
In essence there is a way to do gardening that establishes robustness and drought resistance. I would just call it good practice, and recognising that we all have to be a little bit patient when establishing gardens. How we treat the soil, the use of mulch to conserve moisture, and careful choice of plants all contribute to establishing drought resistance in our gardens. Perhaps the age of ‘instant gardening makeovers’ has passed….I hope so! Happy gardening.