Pruning peach trees is labour intensive. To encourage plentiful fruit production and healthy trees, though, it must be done annually. Timing and technique are the keys to healthy, productive peach trees.
When to prune
The critical aspect of peach tree pruning is timing. Peach trees should be pruned after the last spring frost. If they are pruned too early and a frost occurs, the open cuts can cause damage to the tree. Check local weather forecasts around this time to plan the best date for pruning.
Why prune your peach?
Left unpruned, a number of problems can befall your peach tree. Trees that are not pruned regularly will overproduce, but the fruit is not high quality. Without pruning, the trees are subject to more diseases and shorter lifespans. Another reason for pruning has to do with being able to reach the peaches. Peach trees produce fruit on second-year wood. When the wood gets older, it stops producing. The tree will generate newer branches higher up in the tree to reach sunlight and air flow, making the fruit more difficult to reach.
What to prune
The goal of pruning is promote good health. Clearing space between branches promotes air flow, which in turn helps prevent disease and makes applying insecticides easier. Prune all suckers and water sprouts starting at the bottom of the tree and working up about 90 cm (3 feet). Suckers will develop into another trunk if left to grow, robbing the original tree of nutrients and water. Water sprouts are shoots that grow vertically on the tree. They add shade to the lower part of the tree and fruit does not develop well on them. Next remove all shoots above 2.1 metres (7 feet) high, leaving red shoots that are 46 to 61 cm (18 to 24 inches) in length that will bear fruit this year. Avoid leaving branches at 90-degree angles. Remove any shoots that grow towards the centre of the tree. Remove any grey wood which is the older wood from the fruiting area between the 30 cm (1 foot) and 90 cm (3 feet) range. Cut any branches that are broken. This will limit places where insects can invade your tree. Your goal is to prune back 40 per cent of the tree annually.
After harvest, you can prune new vertical growth. Also prune any damaged shoots or branches as soon as you detect them. Good maintenance practice will help prevent disease and insect problems later. Also remove any limbs that cross. Fruit on these limbs will rub and become damaged.