Managing Exposed and Windy Gardens
It has already been suggested that in many cases a garden exposed to wind is so because the house of which it is a part has been expressly sited to make the most of a desirable view. Thoughts about a garden are apt to follow later; this is unfortunate but understandable.
Yet as a distant prospect of the countryside or seascape is valuable beyond rubies to the environment of house and garden as a whole; it is positively agoraphobic to cut it off. So a balance has to be struck.
The problems are two-fold. These are the providing of sheltered areas for growing flowers and vegetables and for sitting in — there is nothing so cooling as a keen breeze over the hopefully tanning back — and the ensuring that the view is kept open from the main windows of the house. The first decision, therefore, is to answer that old but vital question: What do I want? Should the sitting room open onto an enclosedas an extension of the house for sun-warmed living. Or should a decision permit the eye to travel to the horizon, accepting the corollary that sitting out will have definite limitations. It depends very much what sort of life one leads. Fortunately the two are not quite mutually exclusive and most people will opt for some combination of these facets.
Coping with Exposure
An exposed garden will certainly need to be compartmentalised to provide sheltered corners for plants which resent wind. Obviously notice carefully what does well in the area but it is also wise to think, when choosing plants for windy sites (or indeed any other), in what might be called an ecological way. All plants in the wild are adapted to their habitat. In this situation choose maritime plants or mountain plants for positions of full exposure. Those from bosky or damp valleys will be avoided or especially catered for in contrived protection. The general habits of plants tell us a lot about their requirements even before we turn to the encyclopaedia to check. Wind-resistant plants are apt to be small leaved, often with a shiny cuticle (protective outer ‘skin’) and tight in growth making symmetrical hummocks. Big flaccid leaves would be torn easily and the plant ruined. (An interesting exception, though of little practical value in gardens in these cool temperate islands of ours, is and certain palms, whose great leaves permit tearing in one plane to reduce wind damage. Veins run parallel to the splits so that the leaves’ functions are unimpaired.)
Certain areas of the world are particularly productive of plants for exposed sites. These include New Zealand, maritime California (the Monterey Peninsula provides a splendid pine, Pinus radiata, and the well-known Cupressus macrocarpa) and often the Mediterranean. As many desirable species from these areas lack full frost-hardiness it is as well that a great advantage of many exposed sites is their excellent frost. We are all used to the meteorological forecasts of ‘frost tonight in sheltered areas’. The windy garden does not harbour cold air: it generously passes it on to the protected valley below.
But such sites do call for techniques of cultivation, as well as specialised plants, which cannot be avoided. The most important law which should written large in neon above-shed door, is ‘PLANT SMALL’. Impatience is the devil’s greatest temptation to the keen gardener (he seldom has time for the more colourful of the deadly sins). But plants must be enabled to develop a robust root system to support and anchor the top. Holm oak, Corsican and Monterey pines should go in as one- or at the most two-year-old seedlings only a foot or so high. Started like this they will take full maritime exposure for a couple of centuries, and as they grow a second line of defence of smaller plants can be added. One or two things with naturally dense and heavy rootballs can be planted bigger. These include Griselinia littoralis for mild areas or Rhododendron ponticum where it is colder — but only on acid soils.
Little gardens cannot take, nor do they generally need, tree-sized shelter belts — though it is well to remember that holm oak, for instance, can be kept low by clipping — it is shrub or hedge help that is vital. In the south and west a number of relatively frost-tender evergreens are unsurpassed: Senecio rotundifolius, Griselinia littoralis and Olearia traversii. These will make a dense 3m (10ft) hedge even when there is nothing between them and America. In rather colder areas Escallonia macrantha, Lonicera yunnanensis and Cotoneaster lacteus can take over. Fine British natives such as sea buckthorn (Hippophae rhamnoides) or gorse (Ulex europaeus), the double form U.e. Plenus is best for gardens, should not be neglected.
Obviously a new garden can be greatly helped by some non-plant shelter material. Good walls and fences are of inestimable value but it must be remembered that really solid barriers can create their own problems as wind sweeps round the end or funnels through any gap. Hedges filter and tame it, avoiding draughts. A possible alternative on the Cornish pattern might be more often tried. They create a stone hedge there, which is really a wide, double wall filled with soil with a hedge planted on the top. This gives height more quickly and the problem of the soil-robbing roots of shelter plants using up a lot of space is to some extent contained.
Not until wind protection has been obtained is it worth planting the more usual shrubs and, if they are not to be blown out of the ground and the owner go mad with frustration. When it becomes possible, however, this is the time really to explore the range of plants which not only accept but enjoy the position. Its virtues may be in the south or west and relative freedom from frosts. Clean air is also an expected plus. This is the point to visit local gardens to notice how well, for example, all the lovely New Zealand hebes or the fuchsias do amongst shrubs and what a wide number of South African such as amaryllis, nerines and watsonias relish the position. Permutations are never ending.
Maintenance in an exposed site is an added worry. While planting really small will reduce the need for staking, this can never be entirely avoided. Without it a sudden eddy can drag a plant from its bed like a badly drawn cork. Stakes should be adequate and lasting; so often in a couple of years the plant is supporting the stake. Once the planting hole has been taken out, treeshould be put in before the tree itself, to avoid root damage. Then firm the plant before actually doing the tying. Always after a bad gale go round the staked plants to look for broken supports and chafed bark. It is amazing, too, how rapid trunk growth of, say, a eucalyptus can be ruined within a summer season by overtight ties. Should a plant blow over (and again eucalyptus are particularly prone to this) it is of no use just to jack the thing up and hope for the best. At least half the top must be cut off to reduce resistance. Such rapidly growing plants may need an annual reduction of head to keep top and root in balance.
Much careful research work has been done on the effects of wind movement on cars and aeroplanes and their design reflects this — the current wedge-shape of motor cars is an example.
Observant gardeners do not need research to tell them that the effect on plants is equally dramatic and that some, over evolutionary time, have made many design adaptions to enable them to succeed in windy situations. The wind tortured trees seen on our uplands and coasts show the species that have the strength to grow in unsuitable situations but without really adapting to them.
The diagrams to the right indicate the advantages and disadvantages of solid barriers in the garden as wind shields. In full exposure the strong wall by itself causes more problems than it solves. A combination of both types, carefully sited, is ideal.