Pruning in winter: adjust the tree vigor, standardize the tree shape, concentrate nutrition, delay flowering, rejuvenate and renew, and improve the light by thinning branches, slowly releasing, shrinking four and cutting short.
Pruning in spring: pruning in the late stage of young flourishing branches, slow growth, sparse flower branches, adjusting the proportion of leaves and flower buds to prevent large and small years; 80-90 degrees for auxiliary branches and 70-80 degrees for backbone branches; Carve 0.3 ~ 0.5 cm on the inner buds on both sides of the strong branches to increase the amount of short branches; Erase the buds within 20 cm near the trunk and the buds and competitive buds near the incision to improve the illumination and save nutrients. According to the survey, when young apple trees over 3 years old germinate, the number of branches increases by 36.4%, among which the number of short branches increases by 59%, with an average yield increase of 1 12%.
Summer cutting: The summer cutting period is from late May to early July. In late May, 3-4 leaves were left to twist the auxiliary branches or shoots on the back of the main branches leveled last year, and the flowering rate was 25.2% ~ 39. 1%. From June to early July, the auxiliary branches and temporary lateral branches of young flourishing trees are cut once every 3 ~ 5 cm from the base (to xylem) for three times in a row; When the thickness of the trunk base of the young flourishing tree reaches more than 20 cm in the first fruit period, the number of flowers is 15 times that of the uncut tree, and the main branch 5 cm away from the base is cut three times continuously.
Autumn pruning: mainly carry out branch opening and thinning, and put new branches and competing branches on the back to facilitate ventilation and light transmission.