Unpruned apple trees become twisted and overcrowded, halting their ability to produce quality fruit. Also, unpruned trees usually have only an inch or two of growth each year and tend to produce crops of small, wormy fruit. Pruning young apple trees makes them structurally sound and easy to care for; it also ensures good apple quality. Even long-abandoned apple trees and orchards can be brought back to life with good pruning techniques and growing practices.
The best time to prune apple trees is in the winter dormant season. Winter pruning helps control next season's growth and increases limb strength. Strong limbs hold apples better. Pruning in the dormant season also thins the branches, allowing more sunlight into all areas. Branches that cross each other, are broken or dead are easily removed in the winter when there is no foliage on the tree. Shortening the length of apple tree branches allows the branches to create strong, healthy buds and flowers in spring. Apple trees should be pruned heavily in the first three years to establish a strong structure and pattern of growth. Apple trees are pruned back 20 per cent each year thereafter.
Pruning can also be done right after the apple harvest in summer. Pruning undertaken at this time slows down the growth of trees that are too vigorous or too large. Apple trees that are pruned well are easier to manage. Too much lateral growth needs to be controlled because it is less fruit-bearing. Strong horizontal branches that are well pruned produce the best fruit. Summer pruning is done to remove the leaves, which is the food manufacturing part of the tree. When leaves are removed, growth slows down. Summer pruning is effective when leaves at the top of the tree are removed so the lower branches are exposed to sunlight.
Pruning Old Trees
"A good fruit tree should not make a good shade tree" is the common wisdom about pruning apple trees. Old or abandoned apple trees can be reinvigorated to produce good fruit again by proper pruning techniques. An apple tree that has become a shade tree should be pruned back over the course of two or three years rather than all at once. Pruning should begin in the late dormant season to prevent cold injury to the tree. Prune enough to allow sunlight to reach the lower branches. All deadwood is removed, as well as branches growing across each other. Cuts should be made just beyond a bud or a branch. Apple production will increase steadily the following season.