Key Management Techniques for Jujube Trees After Fruit Harvest
In late June and early July, jujube fruits mature successively and enter the harvest stage. In order to speed up the recovery of tree vigor, promote the growth of robust autumn shoots, cultivate excellent fruiting mother branches, and lay a good foundation for high and stable yields the following year, it is necessary to strengthen orchard cleaning and pruning, fertilizer and water management, and pest and disease control after jujube fruit harvest. The specific measures are as follows:
1. Orchard cleaning and pruning: After jujube fruit harvest, all kinds of weeds, fallen leaves and fallen fruits in the orchard must be removed in time. Remove shaded branches inside the canopy; diseased and pest-infested branches, weak branches, overly dense branches, overlapping branches, dead and dry branches, and branches damaged during harvest on the outside of the canopy; and cut back water sprouts grown from adventitious buds. Then burn them in a centralized place outside the orchard, or dig a pit inside the orchard and bury them deeply.
2. Apply post-harvest fertilizer: Apply post-harvest fertilizer within 5-10 days after jujube fruit harvest, mainly using high-quality organic fertilizer and a complete nitrogen-phosphorus-potassium fertilizer, with supplemental trace elements. For trees more than 5 years old, apply 15-20 kg of decomposed human, livestock and poultry manure, 1-1.5 kg of nitrogen-phosphorus-potassium compound fertilizer, and 0.5-1 kg of zinc sulfate per tree. Dig a ring trench 15-20 cm deep and 15-20 cm wide around the drip line of the canopy, mix all the fertilizers evenly, apply them into the ring trench, and cover with soil.
3. Foliar topdressing: After jujube fruit harvest, spray the leaves once every 7-10 days with a mixture of 0.1% zinc sulfate, 0.1% magnesium sulfate, 0.3% urea, 0.3% monopotassium phosphate, and 1000 times triacontanol, for 3-5 consecutive sprays. This can prevent defoliation after harvest, speed up the recovery of tree vigor, promote and strengthen autumn shoots, and improve the quality of fruiting mother branches.
4. Pest and disease control: After autumn shoots emerge on jujube trees, spray the leaves once each when the new shoots just begin to sprout, unfold leaves, and turn green, using a mixture of 1000 times Lorsban and 800 times Ridomil, or a mixture of 800 times trichlorfon and 600 times Sandofan, or a mixture of 1000 times dichlorvos and 800 times thiophanate-methyl, to eliminate pests and diseases that harm the new shoots.
5. Mulch the tree: After applying post-harvest fertilizer to jujube trees, promptly cover the tree with dry rice straw or other weeds, with a grass thickness of 8-10 cm, to keep the soil moist, improve the effect of post-harvest fertilization, prevent high-temperature and drought weather in summer and autumn from damaging the underground root system, enhance the drought resistance of the plants, and help tree vigor recovery and autumn shoot emergence.