Pruning: How, What and When
Tackling pruning in the garden can be daunting at first, but it is important for healthy and robust trees and shrubs. They benefit hugely from being pruned or even just lightly trimmed to tidy up growth and remove dead, diseased or weak wood. It also encourages shrubs to produce stronger, healthier growth and allows more light and air to reach the plants. Also, pruning gives shrubs a better shape.
When and what to prune
Deciduous trees and shrubs
Winter is the best time to prune deciduous trees and shrubs as it is the dormant season for them, and there is also less risk of pruned branches becoming infected. Try to leave a few berries for the birds when pruning fruiting shrubs.
Evergreen shrubs can be pruned whenever necessary, usually when flowering is finished. However, if the shrub needs to be reshaped the best time to do this is spring. Evergreen hedges can be pruned at any time of the year.
It’s important to know that flowering shrubs should be pruned according to their flowering season to avoid the risk of removing branches that would bear blooms the next season, which would mean the shrub is unable to produce any flowers. Any shrub that flowers in the late winter to early spring should be pruned in late October, directly after flowering, allowing for plenty of new growth during the next summer season. Kerria japonica (Japanese kerria) and Chaenomeles speciosa (flowering quince) are examples of this type of shrub.
Buddleja davidii (butterfly bush), Potentilla fruticosa (shrubby cinquefoil), Hypericum (St John’s wort), Ceratostigma willmottianum (Chinese plumbago), Tecoma capensis (Cape honeysuckle), heliotropes, solanums and Hypoestes aristata (ribbon bush) should all be pruned hard in July to ensure plenty of blooms in late summer and autumn. Overgrown climbers such as clematis, honeysuckle and jasmine will need cutting back to keep them under control and healthy.
Bush roses can be pruned at the end of July, although August is more suitable in the colder temperatures of the Western Cape and the Natal Midlands. Roses are usually deadheaded and trimmed throughout their flowering season to promote more flowers. By pruning the branches in winter, dead wood and leaves can be removed. Roses definitely benefit from hard pruning: they soon grow back bigger and better! Hybrid tea, miniature and standard roses also need some pruning, although hard pruning is not necessary. Climbing roses need to be untied from their supports and the old wood thinned and cut out cleanly at the base. Afterwards, re-attach the rose to the support. Remove and burn any diseased leaves and branches to avoid fungal disease.
The correct time to prune fruit trees will depend on your area, although generally it is between late June, July and early August. In colder parts of South Africa, August is a better time to prune established fruit trees of at least 3 years old. Peach, plum, apple, pear and apricot trees should be pruned by concentrating on the inner branches at the centre of the tree so that air can circulate, and also so that sunlight can penetrate the remaining branches, which will result in a good harvest next season.
Citrus trees rarely need radical pruning – just cut out any dead or diseased wood and thin out if necessary.
How to prune
Before beginning any pruning it’s important to check you have the correct tools you will need for the task:
Secateurs need to be sharp so that the cut is clean. Blunt secateurs will result in ragged, torn cuts which can cause infection. Use secateurs for pruning smaller branches and offshoots.
Loppers are useful for slightly larger, tougher branches, and to tackle much larger, chunkier branches you will need a garden saw. Always wear thick gardening gloves to protect your hands.
It’s a good idea to stand back and take a good look at the tree or shrub before any pruning begins. Once you have decided on the eventual shape, size and height you are hoping to achieve, begin slowly by pruning a few branches and keep stepping back to check the result until you are happy with the results. If you have an overgrown, sprawling shrub with lots of ‘leggy’ branches, it’s worth cutting it right back to encourage young shoots to grow from the base.
When you’ve finished using your tools, make sure you wipe them clean and oil them with a lubrication spray like Q20. This will make them last much longer and prevent them from rusting.
Most of all, don’t be intimidated: pruning can be one of the most rewarding tasks in the garden!