How to Prune Apple Trees
In the past apples were trained into central leader shapes, having a central leader and evenly spaced out branches and stone fruit into vase shapes, however these days many people find the open vase shape easier to maintain and easier to harvest fruit.
In the home orchard the tree will produce plenty of fruit whichever type you use.
As Malus are often grafted or budded, care should be taken to remove suckers, especially those which emerge below the union. When fruiting, pruning is necessary to keep the tree open and prevent crowding. Branches may start drooping from the weight of the fruit. Cut the drooping part back to growth which is almost vertical.
Most apples fruit from spurs which are three to four year old short stems. A few types bear fruit at the tips of long stems and have fewer spurs. The former are known as 'spur bearers' and the latter as 'tip bearers'. Tip bearers make good espaliers and cordons whereas spur bearers are best kept as trees. The type of pruning needed to optimise fruit production will depend on which type of fruit bearer a particular tree is. Regardless of the type, pruning should be undertaken in mid to late winter since apples tend to produce buds in early spring.
Spur bearers need to be pruned by shortening lateral stems. This promotes the growth of spurs. Over successive years the spurs build up although they add smaller and smaller stems each year so they become quite stubby looking. After a number of years the spur system can become quite dense and needs thinning out. When thinning out, the most vigorous leaders are left alone otherwise even denser growth can result.
Tip bearers are pruned by cutting back some of the fruiting stems to a few buds or cut off completely. The remaining fruiting stems are left for several years and then cut to allow new growth to come through.
Larger established trees are often difficult to prune annually and so sometimes a limb is removed instead or a section of a branch. In these cases select branches which are relatively unproductive.
Apples which have been trained as espaliers or cordons can often also need some summer pruning to control shape. New shoots along the stems are cut back throughout the summer to about 15 to 20cm, but only when the base of these shoots is woody enough to withstand any winter frosts.
Open vase shape formative pruning
A vase shaped tree (open centre) tree will eventually have several main branches that will angle outward and upwards from the main trunk. Sometimes a young tree will be bought as a ‘whip’ i.e. a single non-branching stem, cut that back to between 60cm and 90cm long at planting (depending on how low to the ground you want your branches to develop) and wait until the following winter to start your formative training (the whip will send out several side shoots during the first growing season.
The following year choose 3 or 4 well-spaced (around the trunk) lateral branches and cut these back to about 25 cm – trim away any other growth. If your tree had good lateral branches when you planted it, then do exactly the same thing: choose the best 3 or 4 make sure they are well-spaced around the trunk and trim them back to 25cm. These will become the main scaffold of your tree. Now wait until next year to do your next formative pruning.