Includes fixing the trunk and selecting the main branch. After the seedlings are planted, they are cut 40 ~ 60 cm from the ground and dried. Select 3 ~ 4 main branches within 20 ~ 30 cm below the incision. Uniform distribution and moderate opening angle are required. For example, the azimuth angle of the three main branches should be around 120, and the opening angle (bottom angle) should be 50 ~ 65.

There are two specific methods to select, retain and cultivate the three main branches: the first method is that the height of annual single-stem seedlings exceeds the fixed stem height, and three new shoots with good orientation can be selected as the main branches at one time, and the central branches can be erased above the third main branch. Other new shoots are between the first and third main branches, with strong thinning and weak coring control as auxiliary branches. The second is that although the height of annual seedlings exceeds the fixed stem height, less than three main branches are selected from the new branches cut from the fixed stem at one time. First, two branches can be selected (the new shoots below the first main branch are erased). When the central branch from bud cutting grows to about 15cm, coring can be performed, and then 1 qualified secondary branches can be selected as the third main branch. All the parts above the third main branch are removed. The new shoots between the first and third main branches, the strong ones are cut off, and the weak ones are controlled by coring as auxiliary branches.

(2) plastic surgery and pruning in the second year

Refers to the second winter pruning after the seedlings are planted, that is, after the stem is fixed, the main branches are selected for the first year of growth. At this time, the main branches that have not been cultivated for the first time should be pruned at 50 ~ 60 cm. Cut the mouth and leave the outer buds, so that the extended branches extend along the original direction of the main branches. Among the branches with lateral buds below the cutting buds, the eligible branches are selected as the first main branches. For the main branch that has been pruned and cultivated in the summer of the planting year, it should be cut from 45 ~ 50 cm above the first main branch, leaving external buds at the incision, so that the extended branches extend along the original direction of the main branch. Among the branches with lateral buds below the cut buds, the eligible branches are selected as the second main branches. Sub-branches at the same level should be on the same side of their respective branches. It is best to keep a distance of 3 ~ 4 nodes between the branch selected as the secondary main branch and the extended branch of the main branch to avoid competition with the main branch and form the secondary branch. For all kinds of branches that hinder the growth of main branches or auxiliary branches, such as upright strong branches and over-dense branches, they should be thinned by pruning in summer and winter, or controlled by coring.

(3) plastic trimming in the third year

In the same way, select and cultivate the second or third auxiliary branch on each main branch. The opening angle between the auxiliary main branch and the extension line of the main branch should be larger than that of the main branch, preferably 70 ~ 80, so as to maintain a good subordinate relationship with the main branch. The secondary main branches should be properly cut short, generally 1/4 ~ 1/3 can be cut off, and the cut buds are outward leaf buds. The annual branches planted on the biennial branches are mostly fruit branches, among which there are many long fruit branches. Long fruit branches should be properly cut short, about 1/3 should be cut off, and leaf buds should be used as cutting buds. The fruit branch in the middle can be gently decapitated and cut at the leaf bud. Short fruit branches are generally not cut short, and should be properly trimmed when they are too dense. For varieties with high flower buds, the fruiting branches should be cut longer, so that the cut parts will droop after fruiting, and new branches will be drawn from the back, and the next pruning can shrink to the solid fruiting branches.