January is the month that sits on the cusp of the new growing season. Across the country, winter dormancy is still evident, with many regions still experiencing frost or even snow. But as the month goes on, daylight is slowly on the increase and time is ticking on this season.
I enjoy the stillness of this time of year, when most of the garden is still in slumber. There’s the gentle hum of winter-flowering plants doing their utmost to keep our interest in the garden. The perennials left standing from the previous year are patiently waiting to start back into growth in the new season to come. The natural reduction of energy in the garden means it’s the perfect time to prune some of our beloved plants.
In particular, the focus needs to be on the summer-flowering shrubs that rely on the current year’s growth. It’s also the last chance to do any pruning of grapevines, as they can bleed sap if it’s left any later, which can weaken them. As we are technically still in winter, now is also the perfect moment to crown-lift deciduous trees, removing some of their lower branches. As they have no leaves, it’s much easier to see and assess their structure.
Below, I share the plants to prune now and ones to avoid pruning at this time of year. Plus, I give my simple steps to crown lifting a lime tree.
More winter pruning advice:
Plants to prune now:
Before shrubs start into growth, get out your secateurs and cut back those that flower on new stems later in summer. Pruning now will stimulate fresh growth and a good display of blooms.
For colourful winter stems on Cornus, cut the whole shrub down to about 30cm, or take out one in three stems to retain the height.
Prune vigorous Solanum crispum each year to control size and reduce congestion. Cut shoots back to three buds to form a tight framework.
These hydrangeas flower on this year’s growth, so cut stems back to a lower pair of buds for lots of large blooms in summer.
Reduce stems of shrub roses by a third and remove any dead, damaged and diseased wood, to keep an open-centred framework of well-spaced stems.
This is the wrong time of year to prune certain shrubs and trees, because either it would remove the coming year’s flowering stems or it would make the plant susceptible to disease.
- Deutzia: As the flowers are produced on the previous year’s stems, only prune deutzia after flowering later this year.
- Star magnolia: If pruned during dormancy, Magnolia stellata has a tendency to suffer die-back. Instead, lightly prune in early summer.
- Plum trees: Winter pruning plum trees can increase the risk of silver leaf disease, so wait until late spring to remove any diseased or crossing branches.
Step-by-step: Crown lifting a lime tree
Crown lifting simply means removing the lower branches of a tree, and the benefits include:
- Improving access under the tree, especially if a branch is protruding into a walkway.
- Opening up the sight line to a desirable view.
- Letting in more light to plants around the base.
Pruning deciduous trees when they’re dormant and leafless means the tree’s structure is clearly visible, so it’s easier to see what to remove. You may need to use a combination of tools: a pruning saw for thick branches, loppers to reach into the centre of a tree, and secateurs for thin branches.
Look at the tree’s shape and decide how high up the trunk you want the branches to start. If it has many branches, work out which require removal to improve the shape, safety or access underneath the tree. Then decide where the cuts need to be made and choose appropriate tools.
Assess the length and weight of the branch – you may need to support it or reduce its length first, to ensure an easy, clean cut. You should make your cut close to the trunk but not flush against it – leave a small ‘collar’ at the base.
Check the rest of the tree and trim off any branches or twigs that are dead, diseased or damaged. Keep standing back so you can ensure that the shape of the tree remains evenly balanced. Use loppers or secateurs for these smaller stems.
You can use the stems you have removed as hardwood cuttings. This is an excellent way to replicate your favourite trees and shrubs or build up stock for hedges. Trim the stems to 30cm long, cutting the base just below a bud and the top just above. Insert vertically into the ground, so only the top third protrudes. They should root by spring, but avoid moving them until next autumn. They’ll take a few years to reach a good size, but plants grown this way cost nothing and are generally robust.
Other plants to prune this way:
- Trees with a weeping habit may need their lower branches removed, so there’s sufficient space for the cascading branches.
- Multi-stemmed trees look great with clear space under the canopy, so the multiple trunk formation can be admired.