Hard pruning can keep some shrubs in check and stimulate strong regrowth, writes JANE POWERS
I USED TO BE afraid of shrubs and other woody things. Not only are they more of a commitment – in space and outlay – than herbaceous plants, but there is the ever-present possibility of fouling them up by incorrect pruning when they inevitably get too large. (And then, after one has taken the secateurs to them, one is left with a bad-mood-inducing mound of awkward bits of pruned twiggery.)
But shrubs and trees are the backbone of the garden: they give structure and permanence to a space. They provide shelter for other plants, birds and insects. They are too important and valuable to avoid. So, if you’ve been putting it off, it’s time now to make friends with a woody thing. And for those of us who are worried about pruning, there is a group of trees and shrubs that is completely unintimidating in this department. These are the ones that can be radically cut back every year or two, with no harm done to the plant. So there’s no need to get anxious if a once-petite shrub turns into a monster. Instead, you can lop off all its limbs the next spring, and away it goes again. This hard-pruning, known as coppicing or pollarding (depending on where you make the cuts) keeps shrubs and trees to a manageable size, and makes them suitable for smaller gardens.
Coppicing is where the plant is routinely pruned to just a few centimetres from the ground. With pollarding, on the other hand, the cuts are made further up the stem, or along the branches – anything from a metre to several metres above soil level. In time, the tree will form a swollen head at the point or points where it is pollarded. (The word “poll”, meaning head, and “pollard” both come from the same root.) Pollarding requires a little more skill than coppicing, so if you’re new to the secateurs or loppers, try some of the latter first.
Coppicing is always carried out in late winter or early spring, just before the buds begin to swell. Make clean cuts with sharp tools, as ragged edges make it easier for diseases to take hold. After the plant has been through this ordeal it will appreciate some extra care. Give it a nourishing mulch of garden compost or well rotted manure, or a handful of pelleted chicken manure. If the soil is dry, water it well. The resulting prunings, if you are following a yearly regime, will be relatively straight and unbranched, and can be used in the garden to make stakes and plant supports.
The plants that are most commonly treated to a hard pruning are the coloured-stemmed willows (Salix) and dogwoods (Cornus). The brightly-toned twiggy eruptions of the latter are one of the cheering sights along our motorways in the dull days of winter. The new growth that arises after cutting back is vigorous – as pruning always engenders a growth spurt. When autumn comes and the leaves drop, the stems become more richly hued after being exposed to sunlight.
The chalky-stemmed ghost bramble (Rubus cockburnianus) is another woody species that is dealt with in the same way. It is far too robust a grower for a small garden, but if you can give it space, and are rigorous about cutting it back regularly, it is a beautiful thing.
Drastic pruning can produce a different effect in certain other plants: it makes the resulting foliage much larger than normal. The individual most commonly seen treated this way is the foxglove tree (Paulownia tomentosa). Its broad diamond-shaped leaves are fairly large anyway, but when it is cut back in spring, some of the leaves can be 30 or 40 centimetres across, which makes them look marvellously languid, and perfect for tropical-looking planting schemes.
The Indian bean tree (Catalpa), which looks similar to paulownia, but is not related, will also respond with great, jungly foliage if hard-pruned. Eucalyptus gunnii, on the other hand, produces small, spoon-shaped juvenile leaves, which are much loved by flower arrangers.
Not all trees and shrubs are suitable for the dramatic chop: they have to be hardy and vigorous enough to put up with the constant lopping and pruning.
So, if you fancy trying this next spring, chose from list below.
FOR THE CHOP
Acacia, tree of heaven (Ailanthus altissima) catalpa, Judas tree (Cercis), purple hazel (Corylus maxima ‘Purpurea’), smoke bush (Cotinus), dogwood (Cornus), paulownia, willow (Salix), elder (Sambucus).
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Plant sale
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