Reasonable pruning can control the tree potential, improve the ventilation and light transmission conditions of the crown, adjust the balance between trees, promote the formation of flower buds, increase the fruiting parts, avoid the phenomenon of big and small years, prolong the fruiting life of trees, and achieve the purpose of stability, height and Excellence. However, if it is managed extensively or left unchecked, it will often lead to crowded peripheral branches and bare inner cavities, and some of them will move outward. Reasonable pruning can make the tree compact, the branches evenly distributed and the structure reasonable. At present, the trees commonly used in production include natural round head shape, evacuation layered shape and open heart shape. Pruning of plums has different emphases at different ages.
1. Young tree period
Young trees grow vigorously and easily form thick branches. The main task of pruning is to reshape and expand the crown, not only to cultivate a good tree structure, but also to consider the early yield. Therefore, pruning should be light rather than heavy, and in summer, bud thinning and core removal are the main methods. The seedlings should be shortened by 60 ~ 80 cm, and the branches that have been smoked should be reserved purposefully. When the branches grow to 80 cm, the temporary branches should be cored at 60 cm to promote short branches and middle branches to form fruiting branches.
2. Fruiting period
Plums planted for 2 ~ 3 years will soon blossom and bear fruit, forming yield. The purpose of pruning is to continue the plastic work, expand the crown and cultivate as many fruiting branches as possible. When pruning in winter, the backbone branches at all levels should be cut short when the buds are full, and the upright branches and overlapping branches should be thinned out. Pruning, coring, short cutting and thinning should be continued in summer. As long as the position and direction are suitable, we should pay attention to keep the long branches germinate slowly in the crown, do not cut them off, change the branch potential and form fruiting branches.
3. Full fruiting period
After pruning, the tree structure is fully formed, which is the golden age of plum blossom life. The yield increased year by year, but the branch growth decreased, and the reproductive growth was greater than the vegetative growth. During this period, on the basis of strengthening fertilizer and water management, the internal lighting conditions were improved by pruning, controlling the outward migration of fruiting parts, shortening backbone branches at all levels, renewing and cultivating fruiting branches, and thinning out over-dense upright branches. Keep the tree strong and prolong the full fruit period.
4. Curing period
With the increase of tree age, the growth of branches is relatively reduced, and most branches are planted at the periphery and top. The main task is to renew and revitalize the fruiting branches, restore the tree vigor, increase the yield, obtain economic benefits, and cultivate and produce new branches by removing the weak and retaining the strong.