Winter pruning can be carried out after the leaves of peach trees fall and before the germination of the next year, so it is the dormant period of peach trees, so winter pruning is also called dormant pruning. Although pruning can be carried out during dormancy, it is best to prune after defoliation and before the Spring Festival. Young trees of yellow-fleshed peach varieties tend to flourish, so pruning can be postponed until the next spring when they sprout, which can slow down the vegetative growth of trees and prevent flower buds from freezing injury due to pruning before winter. In the cold areas of northeast and northwest, peach trees are mostly cultivated by creeping. In order to facilitate burying in the ground for cold protection, it should be trimmed in time after defoliation and before burying in the ground for cold protection. In areas with low temperature in winter and drought in winter and spring, young trees are prone to bolting (physiological drought). Peach trees in these areas should be pruned before the arrival of severe winter to reduce the branches.

Summer pruning, also known as growth pruning. Pruning in growth period can be divided into spring pruning and summer pruning. Spring pruning can also be called pre-flowering pruning, which should be carried out after germination and before flowering, such as thinning redundant branches and dead branches, cutting short flower branches, retracting auxiliary branches and branches, and adjusting the proportion of flowers, leaves and fruits. Pruning in spring can obviously weaken the tree vigor, so it is mostly used for leafy trees and should not be used for many years. Summer pruning refers to the pruning of the whole growing season after flowering, such as bud smearing, core removal, tip twisting and branch pulling.

Pruning young peach trees in summer can control ineffective growth, save tree nutrition, reduce branch buds, improve lighting conditions, promote robust growth of new shoots, adjust branch extension direction, balance tree growth, prevent overgrowth, accelerate formation, reduce pruning in winter, and achieve early fruit and high yield.

Pruning peach trees in summer can prevent the vigorous branches in the crown from disturbing the tree shape, maintain a clear master-slave relationship, and prevent premature senescence of branches and baldness of backbone branches. Therefore, when the new shoots grow to an appropriate length, summer pruning can be used to control competition and balance the growth of trees. Before flower bud differentiation, pinching new shoots can inhibit the vigorous growth of new shoots, promote nutrient transformation and facilitate the formation of flower buds. At the same time, it is also beneficial to fruit expansion, improve yield and quality, reduce branching parts, slow down the outward migration speed of fruiting parts, promote the healthy development of new shoots, stimulate the germination of secondary buds and increase the branching order. Cutting off the redundant new shoots in the late growth stage can improve the light condition, increase the nutritional storage of the tree and improve the cold resistance and overwintering ability of the branches and buds.

In a word, pruning peach trees in summer will accelerate the formation of young trees, bear fruit early and yield early; It has obvious effects on increasing yield, improving quality, prolonging full fruit period and improving economic benefits of trees.

The common pruning methods of peach trees mainly include: short cutting, thinning, shrinking, sprouting, budding, coring, wringing, pruning, cutting, pulling, cutting or girdling.

(1) To cut short, it is simply to cut short long branches. The function of short cut: enhance branching ability, reduce branching position and enhance the growth of new shoots. Short cut is often used to prune the extended branches of trunk, cultivate fruiting branches or renew and rejuvenate; Short cutting can inhibit the thickening of branches, the expansion of crown and the growth of underground roots. Therefore, young trees and flourishing trees should be cut lightly as far as possible to facilitate early fruit and high yield; For weak trees and old trees, short nodes should be appropriately increased to enhance the tree potential. Another function of short cutting is to weaken the top advantage of branches, adjust the direction of nutrient and water transportation of trees, and improve the nutritional level of branches and buds. Therefore, short cutting can promote the growth of buds under the incision, thus promoting the germination of buds under the incision and the growth of new shoots. The farther away from the incision, the smaller the local lift.

According to the severity, short circuit can be divided into light short circuit, medium short circuit, heavy short circuit, heavy short circuit and extremely heavy short circuit.

(1) Light short shears only cut off the blind nodes of the branches, and the pruning amount is very light. After light and short cutting of peach branches, the germination rate is improved, and the ability of forming branches is also enhanced. The total growth of branches is large, but the growth of branches is not strong. New shoots are mostly concentrated in the middle and upper parts of branches, with full buds, and the lower parts are mostly short branches or leafy branches.

② In general, 1/2 of the total length of annual branches is cut from short and medium branches, and the new shoots sprouting in the second year generally have weak growth potential.

(3) Heavy and short cut is generally 2/3 of the total length of 1 annual branch. The growth potential of new shoots germinated in the second year is generally strong. This pruning method is mostly used to prune fruiting branches, long branches as main branches or extended branches of side branches.

(4) Re-cutting means cutting off 3/4 ~ 4/5 of the total length of 1 annual branches, and the new buds sprouting in the second year have strong growth potential. This pruning method is mostly used to prune extended branches with developing branches as the backbone.

⑤ Extremely heavy cutting is to cut off most of the annual branches of/kloc-0, leaving only 1 ~ 2 buds at the base. This method is mainly used for renewing and pruning long fruit branches.

(2) Thinning is thinning, that is, cutting branches from the base. The function of thinning is to preserve the nutrition of trees, adjust the density of branches, make branches evenly distributed, improve the ventilation and light transmission conditions of crown, promote the healthy growth of new shoots and enhance the ability of flower bud differentiation. Thinning can promote thinning of branches below the position; But it can inhibit and weaken the branches above the thinning position. The thicker the thinning, the more obvious the promotion and inhibition of the upper branches. Thinning reduces the total number of branches and leaves, so the more thinning, the more obvious the inhibition on the whole tree. Thinning is often used in many aspects, such as thinning weak branches, balancing tree length and adjusting branches and leaves.

(3) Shrinking is to cut the perennial branches short, usually to 2-3 years old branches. When the cut branches grow strongly, it can promote the growth of the cut branches and promote the leaf-watching branches near the incision to germinate the vigorous middle and long branches. If the cut part is too big, and the left part and the cut branch are weak, it will inhibit the mother branch too much and sometimes lead to the death of the whole branch. Therefore, when using shrinkage and shearing technology to renew and rejuvenate, it should be handled cautiously according to the strength of branch potential.

(4) The purpose of sprouting tillers is to save tree nutrition and erase the sprouting tillers at the base of the trunk in time.

(5) Bud wiping refers to wiping off the redundant branches and buds near the saw in time after spring germination, wiping off the 1 buds in the two-leaf buds and adjusting the direction and angle of bud cutting.

(6) Generally, when the new branches are 20 ~ 30cm long, competitive branches near the main branches and clustered branches in the inner cavity are removed, or crown expansion, branch promotion and flower bud formation are carried out. Kerning can change the direction of tree nutrition transmission, improve the nutritional level of branches, promote the fullness of buds and promote the formation of flower buds.

(7) Twisting the tip will slightly sprain the base of the branch, making it flat, which can slow down the growth and is beneficial to flowering and fruiting. This method is mostly used for flourishing branches on the back, competitive branches or strong flourishing branches sprouting near scissors and saws. But the number of twisted branches should not be too much, nor should it affect the tree shape. The number of twisted branches should not exceed 10% of the number of twisted branches.

After 1 twist, some overgrown branches are often difficult to restrain, and can be twisted several times continuously or the tip can be twisted first. That is, when the length of new branches is 20 ~ 30 cm, when the secondary branches grow out at 1 ~ 2 times and the total length of new branches is about 30 cm, 1 time can be screwed again, which can increase the number of branches and stabilize the branch group.

(8) When the new branch is semi-lignified, hold the upright strong branch by hand and smooth it slowly from the base to the top. When pruning, the cambium is slightly damaged, and the xylem is not damaged or only slightly damaged. This can temporarily change the transport direction of nutrients, slow down the growth of nutrients, and is conducive to nutrient accumulation and flowering and fruiting.

(9) The principle of cutting tip and coring is the same, and the method is similar. Only when the new shoots grow too vigorously and miss the coring time, can they be cored again, can they be cut off. The effect of cutting tip is similar to coring. Pruning time is slightly later than coring, generally from late May to early June. The shoot cutting time is too late, and the secondary branches are not easy to form flower buds or the quality of flower buds is not good.

(10) Branching is to flatten the upright small-angle backbone branches by bracing or pulling, so as to increase the opening angle, which is beneficial to slow down the vigorous growth of trees, blossom and bear fruit early and prevent baldness at the base. In areas with low temperature, rainy and poor lighting conditions, the opening angle of peach branches should be larger, which can be propped up to 70 ~ 80 degrees; In areas with less rainfall and high light intensity, just hold it down and pull it to about 60 degrees. The time for propping branches is generally from June to July. At this time, the sap flows vigorously, the hardness of branches is small, and it is not easy to break when propping. For young trees with small main branch angle, the main branch angle can be opened by picking the core for many times or replacing the back branches.

(1 1) The method of girdling and cutting to strip a circle of phloem at the base of the branch is called girdling, and the width of girdling should not exceed110 of the branch thickness. Carving is to carve a bud above or below the branch, or above or below the branch, reaching the xylem directly, temporarily cutting off the local nutrient transport path, promoting or inhibiting the germination of the bud and the growth of the branch, increasing the nutrient accumulation and promoting the formation of flower buds. Ring cutting and carving are mostly used for upright strong branches, which can be retracted and trimmed after promoting the results. In order to prevent yellowing or fruit drop caused by too deep and too wide girdling, a certain width of nutrient channel can be reserved when girdling.