When The Wind Blows

I am not a cold person, temperature or temperament wise, but when the wind blows from the north, as it did this weekend, I want to be indoors, with a jumper on and a fire blazing. A penetrating wind blew down from the Arctic on Sunday morning, building to a crescendo by evening. Sitting in my basement ‘snug’ after dinner, the sound emitting from my wood burner sounded like someone attempting to land an A380 on the roof. Rather than showing any concern for the safety of my property, it was out into the garden that I ventured, to see what havoc was being wreaked there. Although the scene was not one of devastation, plants that had remained successfully upright all year were flattened, whilst others had been completely defoliated. The degree of wind-chill, which is effectively the temperature it feels like on the skin, rather than the actual air temperature, was close to freezing. An airborne washing up bowl from next door’s garden almost took a pane of glass out of the greenhouse before landing on my roof.

Wind – and I am talking storms and gales here, not evidently destructive hurricanes – can be one of the most deleterious elements in the garden. Wind cannot be seen and is very difficult to predict and guard against. It may not cause you a problem for months or years, but one day it will come at you from an unexpected direction, causing disproportionate, heartbreaking damage. The same strength of wind in summer may have a very different effect to that in winter. When trees are in full leaf they will filter wind to a degree, but act like giant sails when the wind speed increases. The force exerted by wind rises dramatically as its speed accelerates. More than once I have found myself wrestling with a sopping-wet tree that’s been blown from its stake in a gale, and it’s not amusing. In the winter, deciduous trees are less vulnerable, but shallow-rooted evergreens such as conifers are especially prone to being blown over. Areas of the garden that are well protected in summer may be exposed in winter, which is certainly the case in my own garden.

Changes as seemingly small as the removal of a large shrub or the erection of a fence may completely alter the air flow in your garden, channeling it, dispersing it, creating eddies or areas of shelter. Bigger alterations, such as house extensions on your own or a neighbour’s plot, can have a profound effect. Understanding the adverse impacts wind can have on your garden, and putting in place measures to mitigate them, is as important as knowing your soil type, aspect and rainfall levels. If you have a new garden, this generally involves living with it for a while, observing how degrees of light, shade, moisture and wind vary each season, before deciding what to plant where.

One could write a book on creating shelter from the wind, as anyone who’ has attempted to do it will confirm. It is most assuredly not about putting up a solid fence or growing an impenetrable hedge, both of which can do more harm than good. The most effective windbreaks are formed from multiple pervious layers, be they living or manufactured, which disrupt the force and slow the flow of air passing through them, rather than blocking it altogether. My grandmother’s garden on the north coast of Cornwall had nothing between it and the sea before banks of euonymus, sycamore and pine were planted, their ‘legs’ disguised by a decorative inner fringe of hydrangea. These four companions, in a shelter belt several metres deep, were enough to diffuse the wind across the width of the plot.

Solid barriers such as walls and fences tend to force wind over and around them, creating powerful, destructive eddies. I have an area in my garden, behind the garage that appears to be beautifully sheltered, but which bares the brunt of any wind coming from the south. The air swirls around behind the garage wall like a whirling dervish, toppling anything in its path.

Wind also has a desiccating effect, especially when the air is dry and cold, as is often the case when it blows from the north or east. Transpiration and evaporation of water from the leaf surface is increased by wind, which in turn cools the plant as well as dehydrating it. This negates any positive impact a mild climate might have. This is why, if one wishes to grow tender plants by the coast, one needs shelter as well as warmth. Many plants that thrive at the coast have thick, waxy or heavily-felted leaves, or else fine, willowy leaves that let the air pass through quickly, thus minimising water loss from the leaf surface.

When combined with airborne salt or sand, the effect of wind is tantamount to taking sandpaper to your beloved plants, which no sane person would do. The reason why trees and shrubs growing on cliffs in exposed locations appear to be straining away from the sea is that the sand in the air is destroying the buds on the seaward side, whilst those in the lee are protected and can grow. The resulting silhouette may be dramatic, but the plant is being tortured. Salt in the air is responsible for premature browning of foliage, followed by leaf loss. In my grandmother’s garden the sycamores would typically be stripped of their leaves by mid September.

If you live somewhere very exposed, the best approach is to grow plants that have adapted themselves to the prevailing conditions. In practice, few of us are content to do so, and so we create shelter, prune and stake our precious plants to protects them against wind damage. Clever companion planting can create self-supporting plant communities, and many modern varieties have been bred to make sturdier and more compact plants. Deploying the Chelsea Chop in late May is a good way of cultivating more wind resistent perennials.

My parting advice is never to underestimate the power of the wind. It’s a force far more powerful and unpredictable than extreme cold or heat, in this country at least, and far harder to guard against. Global warming means that freak weather events, including wild and wet winter storms, will become increasingly frequent across the British Isles. Those gardeners who seek to tame the wind do so head on, and live in the knowledge that they’re only one brutal gust away from horticultural Armageddon. TFG.

Categories: Cornish Gardens, Foliage, Garden Design, Musings, Perennials, Plants, Practical Advice, Trees and Shrubs, Weather