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Creating a hedgerow for wildlife
"A hedgerow environment of rich and varied plant communities and of overlapping characteristics of other habitats can offer a multitude of micro-habitats for animal life." Richard and Nina Muir (1987)
WHAT IS A HEDGEROW?
Travellers to Britain will be familiar with hedgerows: linear plantings of shrubs, trees, and thickly tangled vines, 5 metres wide or more, along roads and between fields. Such hedgerows are a magnet for wildlife.
Although it may seem a radical concept, we can also have hedgerows in our urban gardens. Instead of planting the ubiquitous cedar hedge, well-trimmed and manicured, why not try a mixed row of native plant species along with the cedar? Not only will you be providing food, shelter and nesting sites for birds and small animals, but you'll also enhance your property enormously.
HEDGEROWS AND WILDLIFE
Often found along fence lines or drainage ditches, natural hedgerows grow up from wind-dispersed seeds and the droppings of berry- and seed-eating birds and generally contain a variety of shrubs and trees. Left alone, they grow thick and lush, covered in time by vines and edged with wildflowers. This mini-ecosystem has all the key ingredients that an animal needs to survive: food, shelter, nesting and denning sites. Hedgerows can also function as corridors, connecting one patch of habitat to another and offering safe passage to wildlife.
In your garden, hedgerows not only benefit wildlife, they help muffle sound, create privacy, act as windbreaks, and provide a lush backdrop for other plantings. As a visual feast, they are hard to beat.
WHAT MAKES A GOOD HEDGEROW?
Ideally, a hedgerow should be 4 or 5 metres wide, of unlimited length, planted with a variety of berry- and seed-bearing shrubs for food, and interspersed with cedar for added cover. It should be thick, bushy, largely unpruned and entangled with vines.
However, those of us living on small urban plots need not despair. Even a short, narrower hedgerow can be attractive to wildlife, if you follow the basic rules of mixed planting. And if you can convince your neighbours to join you in planting connected hedgerows, so much the better.
Before you begin, take a good look at your property. Decide where you want the hedgerow to go and assess the site for sun, shade, moisture, and wind all of which will influence the types of shrubs you'll be able to plant. Most shrubs require full sun at least part of the day. Do you want a hedgerow that will remain not more than 2 metres tall without pruning? Or would you prefer a tall screen that might require some pruning to contain its growth? Such decisions will also affect your choice of plants. Drawing a simple site plan showing the proposed location and including the various species of shrubs can be useful.
HOW AND WHAT TO PLANT
Gardening books usually suggest planting hedgerow shrubs at intervals of about 1 metre. However, many British hedgerow experts recommend planting 4 shrubs per metre, using plants 45–60 centimetres tall. For a quicker growing, more substantial hedgerow, plant shrubs in two rows 20–30 centimetres apart, using three shrubs per metre.
Planting at this density not only creates a solid wall of growth, it also means that if a shrub dies it will not leave a large gap.
It is best to plant a combination of seed- or nut-bearing shrubs (like speckled alder and hazel) and berry producers (serviceberry, chokecherry, red osier dogwood). Thorny shrubs (wild rose, wild raspberry, hawthorns) give added protection to wildlife.
Once the hedgerow has been in place for a couple of years, plant vines such as Virginia creeper, wild grape, or wild cucumber at varying intervals and encourage them to grow over the hedge. A small city hedgerow won't be able to sustain more than one vine without being overpowered. But a long, thick hedgerow can take vines at widely spaced intervals. The key is not to damage the hedgerow by completely covering it with vines, but to add extra cover and food. Once they are established, you will have to prune heavy grape vines and Virginia creeper annually to allow the shrubs to continue growing. In contrast, wild cucumber vines are annual, very lightweight, and won't need pruning.
For a sunny site, a combination of hawthorn, serviceberry, dogwood, and cedar should work well. Smaller shrubs, such as wild rose and flowering raspberry can be tucked in along the edges. Shady conditions allow for less variety, but try a mix of red-berried elder, hobblebush, cedar, and choke cherry.
Although it is important to water your hedgerow regularly during the first year, once established native plants are almost trouble free.
To prune or not to prune? That is the question many wildlife gardeners ask. Some experts believe that regular hard pruning promotes strong, bushy growth. Others advocate letting plants grow naturally. You'll have to decide for yourself which approach to take. Our preference is for a largely unpruned look, with judicious cutting only where necessary, such as to contain growth of taller species.
WHERE TO SEE LOCAL EXAMPLES
Check out the hedgerow at the Fletcher Wildlife Garden to see some of the plants we suggest. You'll get an idea of their growth pattern and see how closely we've planted to achieve that tangled look. Some great thickets can also be found throughout this area, especially around the old field habitat.
Next time you're out in the country, take a look at the hedgerows around old farms, particularly in the Smiths Falls area.
SHRUBS FOR LOCAL GARDENS
Soil: W = wet, M = moist, D = dry
Check local nurseries for more ideas (many will order native species for you if they don't have them in stock) or contact the FWG at (613) 234-6767 or firstname.lastname@example.org for further information. See also, Planting the urban landscape: Selected trees and shrubs for birds.