Types of Hedging for Your Garden
Which Types of Hedging Plants are Suitable for Your Needs?
Hedges are as much a part of garden layout asand lawns, and can range in size from huge walls of greenery made of yew or beech to decorative edgings of lavender or dwarf box. They demarcate the boundaries and can also make a garden private and sheltered, create a series of separate spaces within a design, or form a backdrop for focal points.
Hedges are a traditional way of defining land ownership. Large, thick and thorny types, such as hawthorn, physically deter intruders and stray animals. (For more thorough protection, reinforcewith chain-link through the centre.)
Smaller hedges can act as boundary markers, though dwarf hedges are liable to be trampled, especially in corners or by short cuts. Some people prefer low boundary hedges, so that their homes are visible from the street to discourage burglars.
If you are considering a shared boundary hedge, it is courteous to discuss your plans with the appropriate neighbours. Legally, you must plant the hedge within your garden, so that it doesn’t encroach on neighbouring property. However, a co-operative neighbour might allow the hedge to be planted on the boundary, and may even be willing to share the cost. It is also polite to discuss the hedge’s height and shape.
Hedges for Shelter
Hedges act as windbreaks and, because they filter wind rather than block it, they can cause less turbulence on their leeward side than more solid walls. Plants benefit from the shelter created by a hedge. Fierce winds have a drying effect on plants, especially newly planted evergreens, and can prove fatal.
On sloping land, hedges can be used to redirect frost, which flows like water, away from the garden. Hedges also offer shelter from dust and their roots help to checkerosion.
The higher the hedge, the more shelter it creates, but it also produces more shade and a greater rain shadow. The larger the hedge, the more water and nutrients it takes from the soil.
Hedges for Privacy
Hedging plants for general privacy should be at least 1.5m (5ft) high, although hedges 1.2m (4ft) high will provide privacy for a seating area. Enormously tall hedges, especially in small gardens, can be overbearing and not worth the extra privacy provided. Hedges planted next to a level change, such as along the top of a retaining wall, seem much higher than they really are when seen from the lower level.
Within the garden, hedges can be used to screen eyesores, such as a dustbin area or shed. Hedges give little actual protection against noise, although they are psychologically soothing and also cut down the glare of car headlights at night.
Hedges as Features
Ornamental dwarf hedges can be used to create pretty, interlocking geometric patterns with the spaces between filled with colourful flowers. These old-fashioned knot and parterre patterns are particularly effective when seen from a raised patio or a first-floor window.
Large hedges can be combined with topiary, with shrubs allowed to grow out at regular intervals, then clipped into geometric or animal shapes. Arches, buttresses and alcoves for seats or statues can be formed out of hedging, given time, space and patience.
Formal or Informal?
In old-fashioned, formal hedges, each plant’s individual character is sacrificed to create an overall geometric shape. Traditional hedges can look as attractive in informal gardens as in formal ones. The straight lines of a formal hedge can complement the ‘rough-and-tumble’ of a mixed border, or an area of long grass and spring bulbs. Formal hedges are particularly suitable for edging small, square or rectangular-shaped gardens, but they require regular, up to four times a year. As a result, they tend to be dense and non-flowering, as the young, flowering wood is constantly removed.
In informal hedges, a plant’s natural shape and habit of growth are the main features to consider. Plants grown in such hedges tend to produce more flowers and berries than rigorously clipped hedges, since less new wood is removed. Escallonia, hydrangea, spiraea and shrubmake excellent informal hedges. Informal hedging of mixed shrubs can lose its ‘architectural’ quality, and look more like a shrub border, which may be exactly what you would prefer.
Dwarf hedges, ideal for edgingor dividing up areas within a garden, can be formal or informal, depending on the choice of plant and pruning treatment. Box, for example, makes a formal dwarf edging; lightly pruned cotton lavender, an informal one.
Evergreen versus Deciduous
Evergreen hedging offers year-round colour and more privacy than deciduous hedging, but apart from a few examples they are insignificant in flower. Deciduous, on the other hand, not only produce flowers in season, but many also have coloured spring foliage, handsome autumn tints and berries, and several, like the hornbeams, beeches and hawthorns, are effective visual screens even in winter when their foliage is brown.
Formal hedges are usually composed of a single species, and are most restful looking this way, but you can combine two or three types of plants for an interesting tapestry effect. Try variegated and green-leaved forms ofor privet, or purple and green-leaved forms of beech. Combining deciduous and evergreen plants makes for winter interest. The proportions can vary, but if the plants vary in vigour or growth rate, be prepared to give the weaker a helping hand. Too many different plant types in one hedge, however, may result in an uneven barrier lacking visual effect.
If you want a flowering or berrying hedge, keep in mind the amount of time it is out of flower or berry, and try to choose a plant that has attractive foliage or form as well.varieties make excellent flowering hedges, and are dog and child-proof. The flowers, which range from white in ‘Blanc Double de Coubert’ to rose-pink in ‘Fru Dagmar Hastrup’ and wine-red in ‘Roseraie de l’Hay’, can be single, semi-double or double, and are freely produced in summer and autumn, often followed by attractive hips. Cotoneaster simonsii produces brilliant berries and richly coloured autumn foliage, and stands hard pruning. Fragrance can come from foliage — rosemary or lavender, for example — as well as from flowers.
Quick-growing evergreen hedging, such as Leyland cypress, is tempting, but it can grow too tall unless cut back vigorously and single plants sometimes die off, creating unattractive gaps. The quicker growing a formal hedge, the more often it needs pruning —three times a year for privet and shrubby honeysuckle (Lonicera nitida), for example. Yew is often thought of as slow, but makes 23- 30cm (9-12in) annual growth, and only needs clipping once a year.
When buying hedging plants, small shrubs are cheaper, less risky to establish and grow more strongly than larger specimens. Always choose plants that are well furnished with branches down to ground level. Make sure you choose the right species or variety for the desired height. For example, Buxus sempervirens ‘Suffruticosa’ is a dwarf edging box while B.s. ‘Handsworthensis’ grows to a height of 3.5m (12ft). Some garden centres have available bare-rooted hornbeam, hawthorn and beech, which are perfectly acceptable if planted when dormant and much less expensive than container-grown specimens.
Hedges can be planted in single or double rows. Single rows are cheaper, and considered better for the ultimate health of the plants, which are less crowded. Against this, it takes longer to make effective screening. Double rows are more expensive and crowd the plants, but are more quickly effective. Space plants 30cm-1m (1-3ft) apart, according to size and growth rate; leave about 45cm (18in) between double rows, staggering the plants.
Pruning regimes vary, but formal hedging must be pruned back hard in the first year after planting, by up to half, to encourage compact growth. Get the rough shape and proportions first, even though it means a temporary loss of height. Formal hedges should be narrower at the top than at the bottom to allow light to reach the lower branches and prevent bare bases. Large-leaved hedging plants, such as Portugal laurel (Prunus lusitanica), look best pruned branch by branch; a once-over with electric hedge clippers or shears is fine for the others. Established formal hedges should be pruned as often as necessary, usually between late spring and late summer
Informal hedges need light pruning to remove old, dead or diseased wood, to keep the hedge within bounds and to encourage flowering. As a general rule, prune flowering shrubs, such as potentilla, which flower on new wood, in winter or early spring; prune those that flower on one-year old wood, such as cherry plum and berberis, immediately after flowering; and prune those that flower on old wood very lightly.