Pruning advice is always a top question for the RHS Members’ Advice Service. Few people have plants that look like those in books and if plants have been pruned heavily in the past or have been neglected or both, it is easy to understand why gardeners should be unsure what to do.
Before digital cameras, pruning advice was a tad frustrating. Describing both plants and pruning in words is difficult and informative pictures were harder to take. But now that members can easily take good pictures that can be emailed to the advice office, pruning advice is pleasure for us and, we hope, gardeners.
Mr L of Milton Keynes sent in two pictures of his slightly overgrown dessert apple tree, published here with his permission.
This tree is actually quite a good tree, but it is clear that several years ago the branches were sawn through to make the tree shorter and the fruit easier to pick. Numerous shoots arose leading to some congested growth and also to the tree becoming a little taller than is ideal.
Many of these shoots have bent down under the weight of crop. This is a good thing as a good crop reduces the vigour of the tree and the branches remain fruitful and the tree has not grown too large for the garden. The first step is to remove any dead, diseased or dying branches. By cutting out a bit at a time you can minimise the risk of a large branch falling and causing damage to the tree. A tip here is to make an under-cut below the branch before cutting from above so that the bark is not torn as the branch falls. Branches that point downwards seldom produce the good flowers or fruit and are best removed.
In this case there are not many branches that need to be removed to be able walk under the tree, but the rather thick growth of branches further up needs to be thinned to one good shoot from each point of origin. In essence, branches are retained that will produce good fruit and these will typically be strong and fairly upward growing, but ideally leaning towards the outside of the canopy. The weight of fruit will cause these to lean out further and this will restrict tree growth and increase fruitfulness in subsequent years, while preventing the tree growing too tall. Also each retained shoot will need at least 1ft (30cm) of space between them and any other remaining branches so that it is not excessively shaded.
When you get up into the tree it is hard to remember what to cut and what not, so it is best to get a helper to check from the ground while you mark the branch to retain – some people tie a strand of string around branches to be retained. The unwanted shoots are then cut back to their point of origin on the main stems.
Finally consider the branches within the tree canopy. This tree appears to have the desirable open centre that lets light into the tree and onto the lower branches, so there seems little need to remove branches from within the tree.
Shortening the remaining upward growing shoots can be left to next year. During the coming year these shoots will probably send out side-shoots at the desirable wide angle that leads to fruitful shoots. Next year the taller shoots can be shortened to a side-shoot which will keep the tree’s height down and promote flowers and fruit.
Subsequent pruning will consist of the normal winter pruning for apples: http://www.rhs.org.uk/advice/profiles1205/applepruning.asp
Mr L says that this tree is about 45 years old and has been cropping for at least 35 years – we think it has potential of several decades more productive growth.