Hedging your bets

So it’s goodbye to those mellow, golden days of early autumn, which have been replaced by a swirl of baleful grey November skies and a cascade of falling leaves.

The latter signals the start of the bare-root/root-ball season, when nurseries and garden centres offer young, field-grown plants for sale, safe in the knowledge that once quickly transplanted into their permanent positions, these dormant or sleeping trees and shrubs have ample opportunity to establish a vigorous root system before spring’s rising temperatures and light levels trigger new growth.

If you’ve been contemplating planting a hedge – one of the most versatile, wildlife-friendly, economical, effective and enduring ways in which to radically transform the “bone structure” of any garden – then now is the best time to do it. Not only will you save money (bare-root or root-balled hedging plants are considerably cheaper than their container-grown equivalents), but planting at this time of the year, while soil temperatures are still high, also optimises the chances of success.

But first, a few words of advice. Begin by giving long and careful thought to the type and size of hedge you want, as well as to its position and function in the garden. Do you want it to define a boundary, to divide the garden internally, to provide a home for wildlife, to offer evergreen shelter and privacy, to screen an ugly eyesore, to filter wind and traffic noise, to deter unwelcome intruders or a mixture of the above?

Whichever species you choose, it should be in keeping both with the garden’s design as well as the wider landscape around it. Boundary hedges of native hawthorn or field maple, for example, are particularly suited to a country garden, as are hornbeam or beech.

In an urban setting, formal evergreen hedges such as yew, Portuguese laurel and low-growing box always look at home. The city garden is also best for brightly coloured hedges such as the evergreen (or should that be ever-red) Photinia ‘Red Robin’ and copper beech, both of which appear strangely alien when set against the backdrop of the rural Irish countryside.

Species for your garden's
growing conditions
All that aside, is the particular species you've chosen suited to your garden's growing conditions? The idea of a neatly clipped box or yew hedge might appeal, but if you garden on heavy, wet, clay soil, then neither is the wisest choice. Instead go for alder, blackthorn, flowering currant, hornbeam or hawthorn, while holly, Cotoneaster franchetti, yew, Portuguese laurel or hornbeam all suit a shady spot.

In exposed coastal gardens, the plants must cope with fierce salt-laden gales, so an informal hedge of olearia, eucalyptus, holm oak, hebe, euonymus Japonica, fuchsia ‘Riccartonii’, rosa rugosa, eleagnus ebbingei, gorse, escallonia or griselinia (or a mix of the above) is a good, wildlife-friendly choice. Even then, young plants will need the protection of sturdily supported windbreak netting until properly established.

Another important consideration is speed of growth. Fast-growing hedges might initially seem a good choice but quickly become a costly and time-consuming burden in terms of upkeep, especially as the garden (and you) grow older. Others present different challenges – the annual trimming of a holly hedge, for example, is a painfully prickly ordeal that many prefer to avoid.

For high hedges, avoid positioning them so that they cause unwanted shade, not only in your own garden but also in your neighbour’s. If unsure, stick a long broom handle in the ground and study where shadows fall.

Remember, too, that a tall hedge sucks moisture and nutrients from the soil, making it difficult for nearby plants to compete. For this reason, as well as for ease of cutting, always leave a generous margin (1m-1.2m) between it and any other planting.

Finally, there is no rule that says your hedge must be a thing of sharp, straight lines and geometric beauty. This can, of course, look lovely, but so can plumply bulging, billowing hedges that have been clipped into irregularly undulating forms more reminiscent of rolling cumulus clouds or distant mountains than of neat, green walls.

Planting a hedge using bare-root/root-ball plants
Preparation is everything when it comes to successfully establishing a hedge, so make sure the site is weed- free and avoid digging when soil is waterlogged or frozen. Once conditions are suitable, dig a trench at least 30cm deep and 45cm wide (twice that if planting in a staggered row or using larger plants), before forking in garden compost/manure. In wet, heavy soils, add grit. Before planting, many nurseries also recommend adding mycorrhizal fungi such as RootGrow.

These beneficial soil micro-organisms help the young plant to quickly establish a healthier, denser root system.

Soak bare- root plants before planting and water the trench itself. Plant to the depth of the old soil mark (visible as a watermark on the stem), then firm down and water well. Keep weed-free, mulched and well-watered until properly established. Pruning requirements vary according to species.