A hedge against invasion
Trespass and privacy are two important issues for ensuring an attractive, peaceful garden, a land untrodden by unwanted interlopers.
Hedges by their very nature, when maintained correctly, create the barrier to deter the intruder and sightseer.
Hedges can be used in addition to the above in other ways – defining parts of the garden, eg separating the veg plot from the ornamental areas, or protecting the fruit garden from invasive species of “outsiders” looking for health food!
Hedges are ideal for keeping out animals, balls and other missiles whilst being a great asset in protection from wind and salt spray.
Selection therefore is important and should be dictated by the “need” ie wind or salt protection, privacy, trespass, ornamental or as a simple barrier.
In windy areas or places of salt laden activity, it is important to use wind- and salt-tolerant plantings of an evergreen nature.
Deciduous species should be used in very protected locations, avoiding open areas and wind tunnels as they can, in windy conditions, be badly damaged to the point of uplifting roots if heavily foliaged.
Evergreen hedges include pittosporum tobira, which is an “old faithful” and withstands a lot of harsh conditions. It also has an attractive white blossom which is highlighted against the deep green foliage.
To be successful it should be given space to grow, especially in width, to obtain a good dense barrier and form.
Constant pruning will, over time, create a plant with thick stems and smaller foliage with nothing growing in the centre of the plant – in other words, growth only on the sides and top.
Casuarina – dare I mention the word! – when used as a hedge is very successful and is an ideal candidate in coastal or exposed areas; when planted at eighteen centres they will fill in quickly.
Carissa is also a candidate for windy areas. It is evergreen, has spines and produces a white, starlike flower, followed by a red/orange fruit.
Japanese yew (Podocarpus macrophyllus) is a conifer that is slow growing in habit but very compact and very hardy; ideal for a medium-sized hedge of four to six feet.
Ornamental hedges are best used in protected areas as most have flowers. Location should dictate type to use as allowance for width is important.
The more you prune the less flower production, as each cut removes potential growth and thus flowering capability.
For a narrow strip of land up to 4ft, consider Cape honeysuckle (Tecomaria capensis), which has an upright habit and “suckers” well to create denseness. The many forms of hibiscus are well worth growing however, if using mixed colours, make sure all types used have the same habit of height and width.
Scotsman’s purse (Malvaviscus arboreus) is quite prolific, producing red or pink flowers. But as the name suggests, they do not open fully.
Texas sage (Leucophyllum frutescens) has grey foliage and is evergreen, the purple flowers stand out against the velvety foliage and add colour to the garden in general.
For use in more formal areas and to highlight a defined area, consider using common box (Buxus sempervirens), which is slow-growing, has small oval leaves and is evergreen. It is ideal to hedge around a herb garden, rose garden or aside the house to stop splashing of rain drip on soil.
When planting a hedge consider the potential size required to determine the planting centres. Oleander, for example, is a very fast grower and can be planted on 5ft to 6ft centres, whereas the Buxus should be planted on 12in centres to visually make an impact.
Whatever the species, when planting I would suggest installing plants in a trench dug to a width of two feet with the same depth.
This will give uniformity of growth in the initial stages which has more immediate visual impact. When purchasing plants, always assess the condition of the plant in its container, not only for pest and disease problems, but also whether the root system is pot-bound.
View the height of the plant against the pot size. A large plant in a small pot indicates the root ball is pot-bound, ie encircling the inside of the pot which will hamper a good root formation once planted.
• Malcolm Griffiths is a trained horticulturalist and fellow of the Chartered Institute of Horticulture in Britain. He is also past president of the Bermuda Horticultural Society, the Bermuda Orchid Society and the Bermuda Botanical Society