What are the key points of orchard management after plum harvest?
1. Apply tree-strengthening fertilizer. After picking, be sure to fertilize promptly and irrigate promptly to restore vitality and strengthen the tree. The fertilizer should be mainly quick-acting nitrogen fertilizer, and the amount applied can be determined by how much fruit was set and how strong or weak the tree is.
2. Pest and disease control
1. Peach green leafhopper. The peach green leafhopper damages leaves; in severe cases it turns the leaves grayish white, weakens the tree, causes early defoliation, and leads to reduced yield or even no harvest the following year. August-September is exactly the period when the peach green leafhopper population is densest and the damage is most severe. Therefore, after picking, great attention must be paid to leafhopper control: first spray the whole tree with Husu Jiangjun for sterilization and disease prevention, then use 50% malathion at 1000 times or 40% Supusha emulsifiable concentrate at 1000 times to kill the insects, effectively inhibiting the production and reproduction of insect eggs.
2. Shot hole disease. Shot hole disease damages leaves and branch tips and occurs in most plum orchards, so it must be controlled promptly. Use 75% chlorothalonil at 700 times, add an appropriate amount of Xin Gao Zhi Mo, and it can be combined with insect control.
3. White peach scale. In plum orchards infested by white peach scale, control should be carried out 1-2 times in early August. Mid-September is the peak occurrence period of the third-generation nymphs of white peach scale, so control must be carried out well. Use 40% Supusha emulsifiable concentrate at 1000 times plus 95% Jiemanling machine oil emulsion at 150 times, and add an appropriate amount of Xin Gao Zhi Mo to break down pest and disease resistance, thereby achieving a thorough insect-killing and disease-preventing effect.
4. Moth and butterfly larvae. For leaf-eating larvae of moths and butterflies, check promptly after picking and control promptly when damage is found.
5. Red spider mite. Red spider mites still cause damage in August-September and must be controlled; the pesticide can be 5% Nisolan emulsifiable concentrate at 1500 times plus 73% Kelunte emulsifiable concentrate at 2000 times. In orchards with severe damage, add an appropriate amount of Xin Gao Zhi Mo to the pesticide to improve insect-killing efficiency.
3. Pruning. After picking the fruit, carry out one pruning, mainly thinning. Cut off competitive branches, densely growing branches, and water sprouts, and adopt the principle of controlling the top to promote the bottom and controlling the outside to promote the inside. In particular, densely growing branches on the outer periphery and upper part of the canopy must be thinned. For plum trees whose canopies are too dense and whose main branches and secondary main branches are too numerous, part of the large branches can first be cut back, and then pruning can be carried out. Through pruning, nutrient consumption can be reduced, the ventilation and light transmission conditions of the canopy can be improved, photosynthetic capacity can be increased, nutrient accumulation in the tree can be increased, flower bud differentiation can be promoted, and flower bud quality can be improved. This lays a good foundation for flowering and fruiting the following spring. After pruning, apply Husu Jiangjun emulsion to the pruning cuts to disinfect and sterilize, protecting the wounds for healthy healing.
4. Deep plowing. In September, deep plowing must be carried out once, with a depth of 20-30 cm being appropriate. This can improve the soil, promote root metabolism and deeper development, improve root absorption capacity, and improve the plum tree's ability to resist drought, poor soil, and pests and diseases. It can effectively improve the plum tree's photosynthetic capacity in the later period and strengthen the tree.
5. Apply sufficient base fertilizer. In September, while deep plowing, apply sufficient base fertilizer; this is the key to achieving stable and high yields throughout the year. Deep plowing combined with base fertilizer application can effectively improve the soil and enhance drought resistance. Applying base fertilizer in autumn, before leaf fall, allows it to be absorbed and used by the roots, helps the roots recover and grow after deep plowing, improves the photosynthetic capacity of the plum tree's leaves in the later period, increases nutrient accumulation in the tree, and benefits growth and fruiting the following year.