Training fruit trees

In order to support the weight of a potentially large fruit or nut crop, it's important to use training in the first few years to create a strong scaffold and branch structure.  Three specific training methods are shown below.

Central Leader | Open Center

Central Leader and Modified Central Leader

In central leader training, the dominant upright branch (trunk) is promoted and other branches are allowed or forced to grow at an angle from it, somewhat resembling a Christmas tree.  Except for dwarf apples, the leader is terminated at a certain height to prevent it from getting too tall.  The length of the leader varies with different tree species.  Apples, pears, and pecans tend to have dominant central leaders and long-lived fruit spurs, characteristics that lend them to the central leader system. 

Walnuts, chestnuts, pistachios, persimmons, figs, and pomegranates are often trained to a modified central leader.  After several (3 to 5) main lateral branches are developed, the leader loses its dominance and is allowed to develop similar to the lateral branches.  Pruning the mature tree involves mostly thinning cuts to allow light to penetrate to lower fruiting wood, although the height of fruit trees should be kept to a height at which fruit can be picked.  Nut trees do not need to be topped.

Dwarf apple tree being trained to a central leader at the Horticulture Center.  Notice the limb spreaders.

Open Center

The open center, or vase-shaped, system is the most commonly used on system and can be used on the majority of fruit trees and almonds.  The center of the tree is kept free of large branches and vigorous shoots, particularly during the growing season, in order to allow sunlight to reach the lower fruiting branches.

Begin by cutting back the tree at knee height at planting (bare root only).  As shoots grow, you can select 3 or 4 shoots to become the main scaffold branches, or you can wait until winter to make the selection.  The branches are headed around 2 to 3 feet long, and two shoots that grow below each cut are later trained upward and outward.  Continue training upward and outward in this fashion until the full height is reached.  Be sure to leave spurs or (for peaches and nectarines) one-year-old branches along the main branches to produce the flowers and fruit.  You can circle a strong rope around the scaffold branches about two-thirds up the tree to support the branches with the weight of the fruit.

Mature open center tree.