Beautiful when in flower, the apricot (Prunus armeniaca) is a small fruit tree that bears deliciously sweet fruits with a hard, stone core. Proper but limited pruning is necessary to form a well-structured tree in its youth, and then light tip pruning every two to three years thereafter to maintain new branch tip growth. Removal of dead, damaged or diseased material is done anytime of year, but primary pruning tasks should be conducted in very early spring.
Pruning of Young Trees
Remove all broken twigs and those located lower than 24 inches up the trunk of a 1-year-old sapling apricot tree. Make a crisp, one-motion cut with the pruner blades 1/4 inch above a bud on a broken branch and 1/5 inch above the connection with another branch or trunk of the young tree. Do this pruning in very early spring before any buds have swollen and opened.
Locate the primary, upright leader stem of the young tree. The "leader" is the natural extension of the trunk that forms the central skeletal spine of the tree. Note if an upright leader is entirely missing or if two or more upright central stems co-dominate.
Cut away co-dominant leader twigs so that only one, straight, upright twig remains. This twig is now the central leader for the young tree. Make the cuts on an unwanted, co-dominant twig 1/4 inch above its junction with another twig or main trunk stem.
Prune off any branches on the tree that have a narrow crotch, those that attach to the main trunk or leader with less than a 45 degree angle. Make the cut 1/5 inch above their attachment to the trunk or leader.
Select three to five branches on the tree to retain as the main "ribs" of the young tree. Severely reduce each branch back to 1/4 inch above one alive, but dormant, bud. Make the cut crisply and in one motion so that no bark tears back and the twig falls away cleanly. The tree will look thin with one central leader and three to five short arms, each with one bud.
Allow the young sapling apricot tree to grow fully the first growing season with no further pruning of its branches and leaves.
Repeat Step 1 in the second year.
Prune away any twigs that are growing straight up, other than the one central leader. Make the cut 1/5 inch above their attachment to a branch.
Cut off any twigs that grow inward across the center of the tree, and those that are growing into or rubbing another branch. Make the cut 1/5 inch above their attachment to a branch. Also remove any branches growing downward.
Trim back, by 6 to 10 inches, any side branch from the trunk that is longer than 30 inches. Make the pruning cut 1/4 inch above a lower, dormant bud.
Select three to four branches on the overall young tree that will become the permanent structural branches. These branches should be healthy and grow slightly upward and outward from the trunk. The central leader of the tree must be one of the branches selected to remain.
Do no further pruning of the tree during the second growing season. But remove any broken or dead twigs anytime they are encountered.
Routine Pruning of Mature Trees
Remove any broken, diseased or damaged branches from a mature apricot tree as needed. Annually evaluating the tree in early spring before buds swell and open is ideal. Also remove any short or scrawny small twigs on the trunk or any branches growing downward.
Lightly tip prune branches on the mature apricot every third year. After three to four years the bud clusters on branch tips may degrade or die. Cutting branch tips back by 6 to 12 inches every third spring helps the tree create new twigs with vigorous new growth that will provide better flowering and fruiting potential. Make these light pruning cuts 1/5 inch above a dormant bud on the branch.
Avoid pruning the tree at all other times of the year and during "off years" in the three-year pruning cycle outlined in Step 2. Prune diseased or dead branches at anytime, however.