Cut it out: a guide to spring pruning
PUBLISHED: 10:00 30 April 2017
What to prune and when, our guide to shedding the dead wood in your garden
As soon as the weather warms up a bit, shrubs, hedges and trees seem to take on a massive growth spurt and it’s time to wield the secateurs.
While first-time gardeners may act with caution, pruning isn’t actually that complicated - the secret is to tackle your plants before they become straggly and out of shape.
Pruning properly should give you more flowers, fruits and general vigour, stripping away old, dead wood and diseased branches, allowing sunlight to the centre of plants to rejuvenate them for the season ahead.
I know some people are worried about cutting plants back too much, but cut a buddleia back hard down to a couple of buds from the ground and you’ll see it tower with fresh blooms in late summer, while cutting back dogwood stems down to the ground will reward you with plenty of fresh, brightly-coloured stems the following season.
So, what should you prune and when?
Most evergreens including conifers don’t need pruning apart from a summer shape-up with shears in the spring. Slow-growing shrubs such as azaleas and hydrangeas also don’t need much pruning and should be allowed to keep their flower heads in winter, which will protect new buds from frost.
Faster-growing deciduous shrubs and trees will need pruning and these fall into two general groups:
:: Those that flower in spring and early summer, including forsythia, philadelphus, kerria and weigela: Flowers are produced on shoots that grew during the previous growing season and should be cut back as soon as they have finished flowering, to allow new shoots to form. Prune them too early, in winter or early spring, and you will cut off the flowers for that year. As soon as the flowers are over, cut back all the stems carrying dead flowers. Follow the stem down until you reach a strong bud and cut just above the point where it grows out on the main branch.
:: Those that flower from early summer onwards, such as buddleia, potentilla and fuschia: Prune in early spring before growth starts, cutting back the old wood (which looks darker and rougher) hard to a low bud, to boost new growth which will give you flowers the same year.
The general rule is if it flowers before mid-June, prune it immediately after flowering; if it flowers later, prune it in late winter or early spring.
Suckers can be a problem on roses and lilac. Remove the basal shoots from the base of the bush or tree, usually below ground, tracing them to the point of origin, cutting them off close to the main stem. The leaves of rose suckers usually have seven leaflets instead of five.
Shrubs which are not totally hardy, such as Choisya ternata, may have been damaged by frost or cold winds during the winter and you’ll need to cut back the damaged leaves at the tips of the shoots to healthy wood, to make the plant look better and reduce the risk of disease.
Eliminate badly crossing branches which are rubbing against each other from shrubs and trees to prevent congested growth and reduce the risk of disease occurring through friction wounds.
If you have variegated plants such as euonymus which are reverting to green, cut out affected shoots when you notice them, as if they take hold, the whole plant could revert.
Clip small-leaved plants and hedges, such as box, with shears or a hedge trimmer if the plant is large. Larger-leaved shrubs such as spotted laurel should be tackled with secateurs as shears can damage leaves which turn brown and then die.
Grey-leaved plants, such as lavender, can receive a light haircut in spring with shears but make sure you don’t cut back into woody old stems, or they won’t recover. Clip them again after they’ve flowered to keep them tidy. Rosemary can also be clipped in spring when it has finished flowering. If you don’t want it to flower, clip it when you see buds starting to form in late spring.
Whatever else you do with your roses, you must prune them every year. Large-flowered rose bushes (hybrid teas and floribundas) need to be pruned between mid-winter and early spring, cutting back all the stems to around 15-23cm above ground level, cutting out dead wood and thin, weak stems. Shrub roses don’t need hard pruning now, but when you deadhead them in summer, remove 10-15cm of stem along with each spent flower.