Plum tree training and pruning methods and key technical points

① Training. The tree form can be natural open-center, multi-main-branch natural form, or “Y”-shape. For young trees, the trunk height is set at 30-50 cm. After sprouting, keep 5-6 buds as main branches; when the main branches are 50-60 cm long, leave 40 cm and pinch off the tips. In August, keep 2-3 permanent main branches, and pull the extra 2-3 main branches apart to make them droop, so they can bloom and bear fruit the following year. Later, as appropriate, train them into medium-to-large fruiting branch groups.

② Pruning. 1) Pinching. When new shoots of the planting year grow to 40-50 cm, pinch off the tips, and pinch 3-4 times per year. When main branches grow unevenly, pinch the extension shoot of vigorous branches earlier and pinch weak branches later. Pinching the secondary shoots on the fruit spur during the vigorous growth period can increase the fruit-setting rate and promote fruit enlargement. In autumn, 15-20 days before new shoots stop growing, pinch off the shoot tips to plump the branches and promote full flower buds. 2) Growing-season pruning. Water sprouts and competing branches should be removed in time. If they are to be trained into fruiting branch groups, from early May to mid-June, cut them back heavily leaving 5-15 cm, twice in succession; in autumn, thin out the medium and long shoots that sprout again, leaving short fruit branches and leaf clusters to train into fruiting branch groups. For weak branches, parallel branches, diseased branches, etc., remove them promptly from the base during the growing season. 3) Dormant-season pruning. Brown plum young trees grow vigorously and have an upright posture, so pruning should follow the principle of “light pruning and long leaving, widening the angle”; scaffold branches and extension branches should be lightly cut back, and auxiliary branches should be left as much as possible to grow slowly without pinching, while overly dense branches are thinned out. To weaken tree vigor, use branch bending on the main and lateral branches to increase the angle; generally the main branches are required to reach a 45-50 degree angle and auxiliary branches a 60-80 degree angle. In short, young trees should be pinched repeatedly on the shoots to promote the formation of short fruit branches and bouquet fruiting branches, increase the number of branching orders, and form an open-shaped canopy as early as possible. Mature trees, however, should control vigorous growth in the upper part of the canopy, thin out many vigorous branches, and cut back weak branches to lead.