Pruning Methods and Suitable Timing for Apricot Trees of Different Ages

​The apricot tree is a relatively common fruit tree in China, with high economic value, so it is grown in many regions. However, to achieve high yields, it is necessary to master certain cultivation techniques and prune it regularly. So how should apricot trees of different ages be pruned? How to cut?

I. Winter pruning of young trees and trees just beginning to bear fruit

Young apricot trees and those that have just entered the fruiting stage generally have particularly vigorous vitality. Both the trunk and the canopy grow rapidly, with strong extension ability and a large amount of new shoot growth, and they often produce many irregular secondary branches. Especially at bends and on straight, extending branches, many vigorous upright shoots are produced. If not handled in time, they easily disrupt the tree shape and affect the growth and development of the scaffold branches. When pruning apricot trees during this period, both the overall shape and fruiting should be taken into account. The main branches and the extension shoots of side branches should be pruned lightly and left long, generally retaining 2/3 of the total branch length for heading cuts. Thin out and remove crowded branches, multi-forked branches, overlapping branches, and vigorous branches that disrupt the tree shape, and control and cut away competing branches and upright vigorous branches. For developing branches with a relatively open angle, leave them unpruned to encourage the sprouting of medium and short branches and increase the number of fruiting branches; after flower bud formation or fruiting, retract them in time to train them into fruiting branch groups. Medium and short branches with wide angles and branches that form flower buds easily should be retained as much as possible, which is favorable for fruiting. For young trees that grow slowly and are not vigorous enough, shorten them appropriately, thin out overly dense and slender weak branches, and retain healthy branches as much as possible to promote the growth of thick, strong medium and short fruiting branches. Train fruiting branch groups. For vigorous vegetative branches sprouting inside the canopy in suitable positions, pinch the tips at the proper time and leave them unpruned for use. When pruning main and side branches at all levels, select and retain plump outward-facing buds so that they continue to extend outward and expand the canopy.

II. Winter pruning of apricot trees in full fruit stage

After 3 to 5 years of training and pruning, the overall structure of a young apricot tree is basically formed, the canopy has begun to take shape, and the proportions of various types of branches are basically fully arranged. As the yield rises year by year, this marks that the fruit tree has entered the full fruit stage. In the early stage of the full fruit period, as the amount of fruiting gradually increases, branch growth in the apricot tree noticeably weakens, and tree vigor gradually moderates. At this stage, the tree's reproductive growth exceeds its vegetative growth, and the amount of pruning is accordingly reduced. When pruning, heading cuts should not be too severe, otherwise they will stimulate vigorous shoots near the cut, inhibit the sprouting of lower buds, and may even cause small branches at the base to decline and die prematurely. Pruning of extension branches and developing branches can be handled flexibly according to the principle of pruning strong branches less and weak branches more. After proper heading of vegetative branches and extension branches, strong new shoots can grow from the top, and fruiting branches can grow from the lower part. If the heading cut is too light, although more fruiting branches can be formed, the new shoots produced at the top will grow weakly, which can easily upset the balance between vegetative growth and reproductive growth, weaken tree vigor, and shorten the years of full fruiting. By the middle and late stages of the full fruit period, the fruiting position begins to shift outward, the base branches begin to become bare, fruit yield gradually declines, and alternate bearing easily occurs. At this time, while strengthening comprehensive fertilizer and water management, reasonable pruning should be used to regulate and maintain vigorous tree growth, balance the relationship between growth and fruiting, prolong the years of full fruiting, and improve economic returns. Although the medium and short fruiting branches and bouquet fruiting branches borne on the main and side branches bear fruit relatively early, they branch little and extend only slowly year by year from the terminal leaf buds. Therefore, this type of fruiting branch has a relatively short lifespan, no more than 5 to 6 years at most. Such fruiting branches play a major role in early high yields, but after entering the full fruit stage, they are more likely to decline and die, causing bare areas. Therefore, starting from the training of young trees, vigorous vegetative branches should be used in a planned way to train larger fruiting branch groups to prevent the inner canopy from becoming bare. Fruiting branches on the upper side of main or side branches have a longer effective fruiting life, but if allowed to grow naturally, they easily form a tree on top of a tree, disrupt the tree shape, and compete with the scaffold branches. If pruning is used to change their direction of extension, that is, from upright to slanting, it can both slow their vigor so they do not compete with the scaffold branches and also allow them to be used for fruiting over the long term.

As the age of the apricot tree increases, fruit production rises and gradually stabilizes, the growth momentum of the trunk gradually weakens, and tree vigor becomes increasingly moderate. At this time, pruning is mainly to maintain tree vigor and prolong the fruiting years of trees in the full fruit stage. When pruning, according to branch vigor and the spatial conditions of each part of the canopy, appropriately thin out overly dense branches and cut back overly weak branches so as to maintain a stable fruiting position and growth vigor. For extension branches at all levels, generally carry out moderate heading cuts (cutting away 1/3 to 2/3 of the current year's growth), so that they produce strong new shoots. For gradually weakening main branches, side branches, perennial auxiliary branches, fruiting branch groups, and drooping branches, retract and renew them at strong branch positions or raise their angles so that they recover their growth vigor. For branches at the lower part and inside the canopy, attention should be paid to pruning, renewal, and rejuvenation so that they continuously produce new, strong fruiting branches. For overly dense branches and vigorous branches at the upper part and periphery of the canopy, retract or thin them out to improve light inside the canopy. Apricot trees have weak branching ability, so for fruiting branch groups, long fruiting branches, and developing branches of moderate vigor in all positions, as long as they are not overly dense, generally do not thin them out; they can be headed back to promote a small number of long branches, allowing the middle and lower parts to produce medium and short branches for alternating fruiting.

III. Winter pruning of apricot trees in the aging stage

In the aging stage, the extension branches of apricot trees grow weakly, new shoots are much shorter than before, scaffold branches begin to droop, the inner part of the canopy begins to become bare, fruiting occurs almost entirely on the surface of the canopy, and apricot yield drops sharply. At this stage, the main task of pruning is to renew the scaffold branches, strengthen the tree's growth vigor, and prolong the fruiting life and years of the apricot tree. Vigorous upper-side branches in the middle and lower parts should be well used for changing the leader. Or retract to a relatively upright branch section to promote the sprouting of latent buds. For well-positioned, reasonable vegetative branches, use pruning to train them into scaffold branches and fruiting branch groups. For fruiting branch groups and fruiting branch limbs, adopt the principle of “remove the weak and retain the strong,” selecting and retaining strong branches and buds for renewal pruning. For trees whose vigor is already extremely weak and for which renewal is difficult to achieve results, field management such as fertilization and watering can be strengthened. Carry out a whole-tree heavy renewal of the growth parts of old apricot trees, removing the entire canopy; in the same year, a large number of new branches and buds can sprout, and through summer bud removal, tip pinching, and winter pruning and shaping, they can bloom and bear fruit the following year, restoring a certain yield or even increasing it.

IV. Issues to note during apricot tree pruning

Apricot trees should be pruned using scientific methods, otherwise it will affect tree growth and fruit quality.

① For pruning extension branches of scaffold branches at all levels, the pruning amount should be controlled at 1/2 to 1/3 of branch length.

② For thin, weak short fruiting branches in the middle and lower parts of the canopy, they should be thinned out in time or retracted and renewed, and the strong branches left behind should also be headed back appropriately.

③ For crossing branches, overlapping branches, and overly dense branches in the middle and upper parts of the canopy, they should be thinned out in time to maintain good ventilation and light conditions inside the canopy.

④ For fruiting branch groups that have borne fruit for years in a row and whose vigor has weakened, appropriately retract them to promote renewed vigor in the base branches and form new fruiting branch groups.

In the late full fruit stage, because of heavy annual bearing (fruiting), the angle of the main branches easily becomes too open, and vegetative branches easily sprout on the upper side of the main branches. Those that can be used should be pinched at the tip when the branch reaches 40 to 50 cm in length to promote branching and train them into fruiting branch groups; for drooping branches on the outer part of the canopy, retract them in time to an upward-growing branch point to raise the branching angle.