The reliance peach tree also known as Prunus persica will reach a height of 15 -- 20 feet when mature. It is hardy in zones 4 -- 9. The main reason to prune fruit trees is to encourage new growth..You want to encourage new growth because the buds that will blossom and produce fruit are actually produced during the previous summer. Although pruning removes some of the fruit buds for the upcoming season, it also produces additional new growth for the next summer's fruiting. Reasons for pruning are to: remove dead, diseased or broken branches; to encourage new growth; and to develop and maintain the open-center structure by removing shoots growing up through the canopy.
Prune any dead, diseased, damaged or broken branches immediately. You can make your cut at the breaking point or you can choose to remove the entire branch. This is a judgment call, which depends on the structure of the tree and the location of the branch or limb that you need to remove. Make a clean cut and don't leave any torn edges, as clean cuts help the tree to heal properly. (Torn and ragged edges can create an entry point for disease.) This can be done at any time -- the tree does not have to be in its dormant stage. Do not place any diseased plant material in your compost bin.
View the structure of your tree. Understand that the structure and shape of your peach tree needs to look like an inverted umbrella. This is called the open-center system.
Remove approximately 30 percent of its old growth to invigorate new growth for the next season. Try to keep the tree short and stocky so that it can hold the weight of the fruit on its branches.
Cut back old wood from the top and sides of the tree -- think of it as giving the tree a haircut. Remove approximately 30 percent of the old wood. This should be done in mid to late February before the leaves appear and when most of the freezing weather is over.
Prune any upward growing shoots or branches that are crossing over within the canopy by cutting them off at their origin. The canopy should be open in the center -- like an inverted umbrella. This is also done in mid to late February.