The only fruit trees that should be pruned in the winter months are apples, pears, quince and medlar. Stone fruits – plums, gages, damsons, cherries, apricots, peaches, nectarines and sweet almonds – must never be pruned in the dormant season (October to March) to prevent possible ingress of diseases such as bacterial canker and silverleaf. I would slightly qualify that by saying that if you discover any damaged branches in stone fruit trees – caused, for example, by bird or wind damage, it is better to trim off the branch to remove any jagged edges and torn bark than leave the damage unattended. In the case of larger breakages and therefore large cuts I suggest that you might smear the cut end with Arbrex Seal & Heal or similar to help seal the wound.
Winter pruning is used in three situations – a) where trees are grown as free standing bush trees or standard trees after the initial framework of branches has been established in the first few years after planting and b) for trees which have become large, well established and possibly overgrown. Generally speaking, the majority of winter pruning will take place during the January to March period (which is why I spent much of my time away from home during this time slot) and c) to go through all trees that were summer pruned to ensure nothing got missed – which it often does!
So starting with a) it should be noted that whilst traditionally spur and tip bearing trees were pruned in different ways this can largely be ignored (and that’s a sigh of relief for many people!) as current pruning methods are very similar in not undertaking a cutting back of all growth. The first thing to do is to cleanly remove all dead, diseased and damaged wood, then remove any very weak branches and eliminate crossing branches rubbing together by cleanly removing the branch that is of least benefit to the tree. After this initial work shorten all of the previous year’s growth to a bud – this will help encourage new branches and spurs. Leave all side shoots i.e. laterals unpruned as you want them to produce fruit buds in the following summer. However, you may need to judiciously remove some of these laterals if they are crossing or there are too many of them. On trees that have been growing for several years you may find some spur systems have become very congested and if this is the case, remove those from the underneath of branches. In the case of tip bearing trees cut back a proportion of the older fruited branches to a young, strong shoot and this will help keep the tree under control without those ever extending branches that are often seen.
If you have a tree of this type that hasn’t been pruned for a few years and has become congested and a little out of control, don’t worry! Firstly, open out the centre of the tree by removing larger branches back to where they emanate and secondly, reduce the height and spread of any branches that have grown too long or big by pruning them back to a fairly vigorous outward and upward facing branch. In future years follow the usual winter pruning regime as I noted above.
Established trees as in b) are more interesting challenges. I am referring here to the big, old garden trees that were probably planted some 50 plus years ago and quite possibly not on anything but fairly vigorous rootstocks. Generally, these trees are left to fend for themselves until the time comes that the branches are totally congested leading to branch die off, fruiting becomes less and less and what fruit there may be is quite high up the tree. This is the situation where I usually get called in. However, it is quite easy to do yourself provided that you have the patience and the wherewithal to dispose of the prunings! You will need to accept that the tree is unlikely to fruit for a couple of years as you will be removing much of the fruiting wood.
What you are looking to achieve here is to get back to a basic tree framework and bringing the height of the tree right down. The first thing to do is to remove all dead, diseased and damaged wood, all water shoots (and there are likely to be many) and cut out wood as required to prevent crossing branches. You will already have taken quite a lot of wood out of the tree. The next thing to do is to clear out the middle of the tree by removing any branches that are growing inwards. These branches are unlikely to produce any fruit and if they do, the fruit will never ripen well or colour up. Now decide what height you would like the tree to start growing at again so that you are going to be able to harvest the fruit. I always aim to cut all branches back to around 2.5m (8ft) from ground level. By cutting back to this height you will still end up with a tree of some majesty but far more useful for cropping and harvesting. You can of course, cut back to a lower height or a not so low height and this is entirely up to you and the tree’s location in your garden. Once you have cut back to the required height, shorten all laterals off the branch framework to around 15cm (6in). Your trees will now look quite bare but this rejuvenation will quickly inspire the tree to grow plenty of new wood.
There has to be a double health warning here. Firstly, the majority of ‘experts’ will advise you to heavily prune trees like this over a two or three-year period to stop the tree declining rapidly. I, personally, have never followed this principle and in the hundreds and hundreds of trees that I have renovated I have never had a failure yet! In any case most clients of mine don’t want to see a half finished tree let alone pay for two or three visits. The second health warning is that these trees are likely to go ballistic for the first year or so as they have been reinvigorated so much! The important thing to do is respond by pruning all new growth hard every winter and keeping your new height and removing the hundreds of water shoots that are going to appear.
And the final reason for a winter prune is c). This is a quite easy operation as it simply involves having a good look through all of the restricted forms of trees that you pruned during the summer i.e. cordons, espaliers, fans and dwarf bush trees, to ensure that you missed nothing during the summer prune. When trees are in full leaf it can be easy to miss the odd lateral that you should have pruned back then. Additionally, you might accidentally have caused some damage whilst picking fruit or the winter birds may have been feeding on hanging fruit and damaged a lateral or branch by their weight. Winter is the time to rectify all of these issues.
Fortunately there are plenty of winter days which are sunny and warm when you can do your winter pruning but think of poor me and my team pruning all of those big trees in the foulest of weathers. As we only have a short window rain, frost and snow can’t stop us!
31st January 2016
Gerry is an experienced amateur fruit grower who is Chairman of the RHS Fruit Group, a member of the Royal Horticultural Society’s Fruit, Vegetable and Herb Committee and also their Fruit Trials Panel. Gerry judges fruit nationally for the Royal Horticultural Society and is also a qualified National Vegetable Society judge.