Grapefruit has strong growth potential, vigorous growth of new shoots, high crown, large leaves and large fruits. Adult tree 1~2-year-old spring shoots are its main fruiting mother branches, and perennial inner-bore branchlets also perform well. There are most leafless fruiting branches, and the shape of pomelo trees should be changed to trunk or natural round head, with few and sparse main branches and more branches. The pruning of adult trees is mainly thinning, the strong ones are removed, the weak ones are left, and the short ones are supplemented. Only spring shoots are released once a year to control summer shoots and autumn shoots.

(1) When grapefruit enters the full fruit-bearing stage, it is necessary to make full use of the fruits of spring shoots, erase the summer shoots and autumn shoots before turning green, and cultivate moderate and robust fruit-bearing branches of spring shoots, which is the basis of high yield of grapefruit.

(2) The inner branches, oblique branches, drooping branches and leafless branches under young pomelo trees are the main fruiting branches, which should be kept as much as possible when pruning. When thinning the spring shoots, trim the strong branches that are upright and upturned, and leave the drooping middle branches in the inner layer. Perennial branchlets and leafless branches planted on all branches of adult trees are also excellent fruiting mother branches and should be preserved. After fruiting, cut it short from the vegetative branches or healthy leaves.

(3) Pomelo flowers are racemes, with large inflorescences and many flowers, so it is necessary to sparse flowers and fruits. When sprout soybean is big, it begins to be sparse. First, the inflorescences are sparse, then the small inflorescences and dense inflorescences are cut off, and the strong inflorescences are kept. Each bearing branch keeps 1~2 inflorescences. Sparse flower buds before flowering, first sparse deformed flower buds, then sparse small flower buds on the upper and lower parts of inflorescence, leaving 2~3 large flower buds in the middle. After the second physiological fruit drop (20~30 days after flowering), fruit thinning is started, and the pests, deformed fruits and small fruits are thinned for the first time; The second thinning of double fruits, small fruits and dense fruits among the three fruits, leaves 1~2 fruits on each mother branch, due to the fixed fruit and yield of the tree.

(4) Wang Shu and Wang Zhi used girdling, girdling, girdling main branches and auxiliary main branches to promote flower bud differentiation from mid-late September to late June; The above measures can also protect the fruit after the bud begins to wither. Surrounded only by lush trees and branches. Young trees can inhibit vigorous growth and promote early fruit.