Fruit tree pruning
It may lean over its neighbours or have overgrown its spot, but you cannot treat a neglected apple or pear (pictured left) – one that has not regularly been pruned – with a short back and sides. Radical pruning of apples is always disastrous, because it results in more vigorous growth. It may look like you’ve solved your problem, but next spring, the tree will sprout a mass of watershoots. These are vigorous non-fruiting, vertical shoots produced to restore the balance of roots to shoots. Instead, in any one year, aim to take off no more than 25% of the canopy.
Standard apple and pear trees are pruned into a goblet shape with an open middle for air circulation and light, and equally placed framework of limbs, usually four to five main branches roughly 50-60cm apart. If it has not been pruned for a while, start by removing branches in the centre of the tree to open it up. You may need to take them right the way back to the main framework or point of origin. However, resist the temptation to prune off large limbs – avoid cutting off anything bigger than 20cm in diameter. If, by thinning out the middle, you have already taken off your 25%, then stop. No more pruning until next year.
Next take out anything diseased, dead, dying or damaged, as well as those that are crossing and rubbing. This usually decongests the tree and restores a sense of balance.
You may still need to reduce the height and spread of branches that have grown too large. But don’t just trim off the top of the tree, because that will result in a thicket of new growth where you’ve cut with little of this growth fruiting – particularly if you have a tip- or partial tip-bearing tree such as a bramley or discovery (fruit produced at the tip of the previous year’s fruit) – and you’ll have removed the majority of the fruiting wood.
To reduce the size of a branch, cut back to an outward- and upward-facing, vigorous lower side branch. There’s a rule about ratio: you shouldn’t cut a big fat branch back to a wimpy twig of a side branch; and the lower branch has to be at least one-third the diameter of the branch being removed. Next, remove any lower branches that receive little light and get in the way of moving around the tree.
Finally, in spur bearers (trees that produce fruit on short branched shoots), remove or thin out any spur systems that have become congested: spurs need to be 10-15cm apart along the branch. Remove the spurs on the underside of the branches, because these will produce fruit that won’t receive enough light and will be inferior