|Winter pruning is essential to let light and air into the orchard canopy.|
Winter pruning, carried out when trees are dormant, is one of the most important seasonal orchard jobs. It is essential routine maintenance, necessary for the health and vigour of the trees and also helps maintain overall orchard hygiene.
Trees are basically powered by sunlight and for fruiting trees this is one of the most crucial elements in how they perform. Many pests and diseases flourish in still, damp conditions and so good air flow is vital in providing control systems, especially against scab and mildew. Keeping the canopy open to allow ample light and sufficient air is a key management principle. My father used to sum this up in the maxim that when he had finished pruning a tree he should be able to throw his hat through it.
A second principle is as simple as ABCD. This signifies that you should Attack Broken Crossed and Diseased branches. Broken branches can let in disease and may damage healthy growth. Crossed branches will interfere with light and can cause rubbing and damage bark and anything diseased needs to be removed and burnt. In older orchards dead wood can be left as it can provide excellent habitat for many species and help maintain good biodiversity.
The third basic reason for winter pruning is to ensure the vigour of the tree. If the tree senses it is under threat or attack it will be stimulated or encouraged into a positive reaction. It will be reminded of the basic need to reproduce, encouraged to throw fruit bud and hence more fruit. Its reaction will depend on its root stock, age and condition, but as a general principle winter pruning will encourage or maintain the vigour of the tree.
So, if you remember to “Throw your hat”, go for ABCD and balance the vigour of the tree, you are well on your way to understanding the Principles of Pruning or The Art of Farming Light and Air.