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FTPF Factsheet: Pruning Fruit Trees
Fruit trees may be pruned every year to encourage balanced growth and productivity and, if necessary, control their size and shape. Pruning is a dwarfing process that may result in a slight reduction in yield compared to an unpruned tree, however, the size, color, and quality of the remaining fruit, and the health of the tree, will be improved. Summarized, the objectives of pruning are to:
1. Develop strong tree structure: Best begun shortly after when trees are planted & continued annually
2. Provide for light penetration: Good light quality throughout the tree increases fruit bud development for following years and increases the quality of the current crop.
3. Control tree size: If size is an issue, trees may be pruned to control branch spread and tree height.
4. Stimulate new growth. Pruning serves to encourage growth, resulting in new fruit-bearing areas.
5. Remove damaged wood: Some wood damage occurs from such things as wind damage, fruit weight, winter injury, disease, and insects.
When to prune
The best time to prune is during late winter or early spring, just before the beginning of active growth. It is important that you finish pruning just prior to bud break. It will not necessarily harm trees if sap is beginning to flow at the time you prune. The main reasons you should prune during the late dormant period are because:
1. Wounds heal quickly when growth starts
2. Undesirable branches & damaged wood can be easily identified when there are no leaves on the tree
3. The bark is less likely to tear when cuts are made
4. Trees pruned in early winter (as opposed to late winter) may be damaged by low winter temperatures that occur after pruning.
Note: While late winter/early spring pruning is recommended, please keep in mind that summer pruning may be used to control growth of young trees, improve light quality in the fruiting zone, thin heavy fruit loads, or remove water sprouts, suckers and other undesirable wood.
Pruning for the general health of the tree
Vase (open center, multiple leader): Head the tree to a short trunk at planting about 18 to 30 inches above the ground with 3 or 4 main or scaffold limbs, each being fully filled-out secondary branches. Scaffold limbs should start at about 1 to 2 feet above the ground. The vertical distance between each scaffold branch should be 6 to 8 inches. This shape offers the advantage of an open center so light can penetrate to all branches. Always use vase pruning with almond, apricot, fig, filbert, nectarine, plum and peach trees and often with apples, cherries, pears, and olives.
Modified central leader: Shape the tree to one tall trunk that extends upward, emerging clearly at the top. Remove the leader after 2 to 3 tiers or until the basic framework is established. This shape makes a strong tree with well-spaced scaffold branches but with less fruit, since the center is shaded. This type of pruning works well for dwarf or semi-dwarf trees, since these types are so small that increased shade does not pose a problem. May be used on apricot, cherry, pear, persimmon, plum and walnut trees, but do not use this method on most standard-sized fruit trees.
Central leader: Train the tree to develop a tall, narrow framework. Central leader training avoids problems caused by tree spreading. This method is especially useful with dwarf and semi-dwarf trees to allow for easier harvesting. Let the leader grow and head back from 2 or 3 feet above the lower whorl of branches from the previous year. May be used on apple, cherry, pear, persimmon, plum and walnut trees.
Pruning techniques for specific tree types
Almonds: Prune to vase; fruit produced on 1-year old wood; encourage erect growth; remove last year's fruiting wood except for 1-2 new shoots
Apples: Prune standards to vase, prune dwarfs and semi-dwarfs to modified central leader; use mainly thinning cuts for size control; prevent excessive vertical growth by shortening branches by 2/3 to a fruit spur, if possible; fruiting wood on older branches generally show as short fruit spurs
Apricots: prune to vase; remove 1/3 of new wood each year by heading and thinning; find fruiting wood by looking for fattest bud at the end of 1 year old wood; do not head back l-year old shoots; thin fruit to 4-6 inches apart when olive-size; Note: Some apricots may bear fruit on the center section of 1 year old wood and should be headed back by 1/3. Other types may produce their fruit on the lower section of 1 year old wood and should be headed back by 1/2 to 2/3 their length.
Apricots (Semi-dwarf): prune to modified-central leader; fruits mainly on older spurs; remove 1/3 of new wood each year by heading and thinning; create a "stubby" look; thin fruit to 4 inches apart when olive-size
Cherries (sour and sweet): Prune to any of three methods; thin branches only to maintain general shape and to remove tangled appearance
Dwarf trees: Prune to modified-central leader; prune only enough to create an open branch structure; thin fruit severely to maintain quality
Figs (white and brown varieties such as Kadota, Thompson, Brown Turkey): Prune to vase; Prune less than most other fruit trees; Remove medium size limbs occasionally to reinforce strong structure; head last year's wood back to a 2 buds
Figs (black varieties such as Mission, San Pedro): Prune to vase; fruit on one-year-old wood; prune only to evenly spaced branches and to remove rubbing limbs
Nectarines: Prune to vase; select the strongest branches with the most amount of lateral twig growth for the fruiting wood; thin out approximately 2/3 of last year’s shoots so that fruiting twigs are 8 – 12 inches apart; fruits on center 1/3 of last year’s wood; clip back remaining fruiting twigs (1-year old wood) by 1/3
Peaches: Prune to vase; fruits on last year's wood; prune hardest of stone fruits; reinforce natural structure to improve fruit-holding strength; prune at least 2/3 of last year's shoots to 8-12 inches apart; clip back remaining shoots by 1/3 to 2/3; fruits on center 1/3 of last year’s wood; thin fruit to 8-12 inches apart when olive-sized
Pears (Asian): Prune to vase or modified central leader; bears fruit best on 2-3 year old wood; develop multiple leaders and strong lateral growth; remove most of new vertical shoots each year, then head long shoots back to a flower bud before blooming; thin ends of branches after fruit set to ensure that heavier wood holds the fruit; prune Asian pears a little more severely than common pears
Persimmons: Prune to central leader or modified-central leader; thin very lightly each year to keep an open structure; remove branches that grow downward and those that have lowered closer to the ground; may head back excessive lateral growth to encourage branching; fruit is borne on current and last season’s growth
Plums: Prune to vase or central leader; fruits on 1-year old laterals and long-lived spurs; evenly thin previous seasons growth; shorten 1-year old wood by 1/3; remove new growth that is crowded
Pomegranates: Prune to vase; prune mainly by thinning to keep tree open and fruit accessible; remove suckers and excessive water sprouts
Walnut: Train as a central leader in youth; develop strong limb structure; may head back long lateral growth
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