Pruning of cherries is divided into three times: summer pruning, autumn pruning and winter pruning, with summer pruning and winter pruning as the main methods.
(1) Pruning in summer
The purpose of pruning in summer is to improve the lighting conditions, reduce the ineffective growth of new shoots, and make the tree form early, blossom early and bear fruit early. The main pruning methods are: sprouting, twisting branches, thinning branches, taking branches, coring, ultra-short cutting and so on.
sprout removal and bud wiping: all the competitive buds of the main branches, lateral branches, strong branches and extended branches near the big cutting opening are erased at the leaf cluster stage. Cut off double buds and leave single buds, dry branches, branches of diseases and insect pests, waste buds and reduce long fruit branches that are not set. The sprouting of rootstocks should be cut off as soon as possible. By removing sprouting and smearing buds, useless new shoots can be reduced, nutrients can be concentrated, and the remaining branches can be fully developed, and the flower buds and leaf buds are full. Bud smearing and sprouting removal can improve the light condition of the crown and greatly reduce the workload of summer pruning and the wounds caused by summer pruning branches.
Twisting branches: Twisting branches mainly refers to the long branches in the parts where there are few branches or the main side branches are prone to sunburn. When the new shoots are semi-lignified, the competitive branches near the main branches and the extended branches of the side branches, and the strong and prosperous long branches and upright branches that have space to be used as side branches or large and medium-sized fruiting branches are cut off.
thinning: mainly thinning the over-dense branches on the main lateral branches and fruiting branches from the base. The amount of thinning should be controlled at 1/3 of the number of new shoots in the thinning position, and not too many branches should be thinned at one time.
taking branches: mainly by taking branches to change the growth orientation of 6 cm long lateral shoots with overgrowth characteristics at high temperature.
coring: coring can easily lead to too many secondary shoots and a closed crown. At present, except for the pruning of young trees, it is necessary to coring the main lateral branches, and summer pruning generally does not advocate coring new shoots.
ultra-short cutting: before June, the long branches with space on the main backbone branches can leave 1-2 nodes at the base for ultra-short cutting, which can cultivate small and medium-sized fruiting branches.
(2) winter pruning
winter pruning refers to pruning after the tree enters winter dormancy. Its main methods are: short cutting, slow release, retraction, thinning and so on.
thinning: thinning branches from the base is called thinning, also called pruning. Thinning branches can improve the ventilation condition of the crown, reduce the density of branches in the crown, make the storage nutrition in the tree relatively concentrated and promote the growth of new shoots; After pruning, it will inhibit the upper part of the wound and promote the lower part of the wound. Removing useless branches that are thin, diseased, overgrown, overlapped and densely shaded can promote the growth of the remaining branches.
retraction: refers to the short cutting of perennial branches, also known as reduction. Retraction can supply nutrients and water to the remaining branches, promote the growth of the lower branches, and is beneficial to rejuvenating the tree. Its function is to improve the light condition in the crown, reduce the fruiting position, change the extension direction and angle of the extension branches, control the crown and prolong the fruiting period.
short cutting: cutting off part of annual branches is called short cutting. There must be leaf buds under the cut of short branches. The function of short cutting is to reduce the number of leaf buds and flower buds on the short cut branches, strengthen the growth ability of new shoots from the short cut branches, reduce the branching position and enhance the branching ability. Light and short cutting: cutting off less than 1/5 of the total length of annual branches, the growth potential of new shoots germinated next year is weak, but the number of new shoots is large, which is mostly used for cultivating medium, short and bouquet-shaped fruit branches. Or after cutting the strong fruiting branches lightly, increase the number of fruiting branches and control the growth of new shoots. Medium-short cutting: 1/2 of the total length of the annual branch is cut off, and there are full buds under the cutting mouth. The new shoots germinated next year have strong growth potential and a large number of strong new shoots are produced, which are mostly used for pruning the extended branches of the main side branches. Heavy and short cutting: 2/3~3/4 of the total length of annual branches are cut off, and the plumpness of buds under the cutting mouth is poor, but the pruning amount is large, so the new shoots sprouting next year have stronger growth potential, but the number of new shoots is small, which is mostly used for controlling pruning of strong branches. Extremely heavy and short cut: more than 5/6 of the total length of the annual branch is cut off, and the sprouting branches in the next year are weak. This cutting method is mostly used to cultivate fruiting branches with developing branches and overgrowth fruiting branches.
long release: annual branches are not cut and allowed to grow naturally. Prolonged fruiting branches or long fruiting branches with excessive growth potential can weaken the top advantage and promote the formation of short and medium fruiting branches. Long-term planting can keep the most buds on branches and slow down the growth of new shoots in the next year.
(3) Autumn pruning
Autumn pruning is a necessary supplement to summer pruning and winter pruning. Because the growth is basically in a semi-stop state after entering autumn, the tree body is not sensitive to pruning. Cutting off the light green tips of the branches of the current year can save nutrition and promote the development and enrichment of the branches themselves, flower buds and leaf buds. Appropriately thinning the over-dense branches with shading on the periphery, retracting the long branches by 1/3, opening the light path, promoting the development and enrichment of the branches in the inner chamber, and coating protective agents on the large scissors to promote healing.
As the saying goes, cherries are delicious but difficult to plant. In order to create good growth conditions for cherry trees, so that they can bear beautiful fruits every year, pruning plays an increasingly critical role as an essential technology for scientific management of cherries and increasing production and efficiency. Under normal circumstances, small cherry trees should be trimmed into vase-shaped (spindle-shaped) to promote the circulation of light and air, so that the air can be fully distributed around the branches. After entering the young adult period, the dead branches and infected parts should be cleaned up in time every year to ensure the health and strength of the tree. Specific in the pruning, should also distinguish the specific situation, avoid copying mechanically. Mainly should pay attention to: First, the pruning method should be determined according to the characteristics of varieties, tree age, tree potential, planting density, cultivation methods, cultivation level and so on. In addition, we should pay attention to the reaction after pruning and adjust it in time when problems are found. Second, when thinning branches, it should not be too much at one time. If thinning is necessary, it should also be carried out step by step in different years, and timely and appropriate amounts should be mastered to prevent haste. When thinning large branches, the wound should be smooth without leaving branches, and the wound is inclined or downward. It is most forbidden to cut into "sky scar" wounds and apply wound protectant after disinfection. Third, the twisted tip should be carried out at the semi-lignified part of the new tip. In addition, the twisting tip should be operated by hand and cannot be replaced by pliers. Washing and cutting branches and leaves with dirty and blunt pruning shears will make them infected with diseases. Make sure your scissors are sharp so that they won't damage the branches when pruning. Be careful to disinfect the pruning shears before pruning your tree every time. Fourth, some varieties, such as chicken heart and short purple, will weaken the number and growth of developing branches and even form small old trees, which should be paid special attention to.