The first few years of growth, pruning a young pear tree is important to achieve a shape that promotes maximum light exposure and air circulation. The goal of pruning a pear tree results in branches that are similar in size and grow at uniform distances horizontally around the trunk, forming a tree with a broad bottom and narrow top. Branches that overgrow others and cause too much shading require complete removal, as well as branches growing lower than 20 inches above the ground. Most pruning should be done during the dormant season from late winter to early spring.
Trim the central leader the first year so the young pear tree is between 24 to 40 inches tall and cut back any branches that compete with the leader. The central leader develops into the main trunk of the tree.
Identify the largest, strongest limbs and cut all smaller limbs completely off at the trunk. Leave three to six branches evenly spaced around the trunk with at least 6 inches between them vertically.
Trim the large, strong branches that are left to remove about half of the terminal growth, which is the leggy, twiggy branches at the ends of the larger branches.
Cut back any broken branches or branches that meet the trunk at a 45-degree or smaller angle.
Use a tree training stake or limb spreader if necessary to train the branches to grow horizontally from the trunk. Horizontal growth encourages production of flowers and pears rather than branches and leaves.
Train the central leader of the young pear tree with a stake if necessary so that it grows straight.
Remove branches that are larger than 1/2 the diameter of the trunk at the point where it joins the trunk.
Trim the branches in the second and third years so they are all about the same size, located at even intervals around the trunk, but do not shade lower limbs.
Cut back the central leader to keep the tree from growing taller than 20 feet. This helps encourage development of the side branches, also known as scaffolding branches.
Head back the chosen scaffolding branches during the first few years after planting to encourage strengthening and development. "Heading back" or "heading" involves cutting back the multiple long, twiggy branches at the end of the scaffolding branches, also known as "terminal growth."
Trim out small branches growing vertically up or down from the scaffolding branches; branches that have grown tall enough to compete with the leader; small, interior branches that are shaded by others, and branches that are growing crossed over each other.
Make sure the tools are sharp so the cuts are clean to reduce damage and stress. Dispose of the trimmed branches away from the young pear trees so they do not attract insects and diseases.