Key points of cold prevention of longan in winter

1. Cultivate strong autumn shoots. Autumn shoot is the mother branch of longan in the coming year, and it is also one of the main branches of longan overwintering. Whether the autumn shoot is strong or not affects its ability to survive the winter. Therefore, it is better to control the last autumn shoot of longan in mid-late October, and it is best to apply nitrogen fertilizer and water once before shoot release, so as to strive for the maturity of all autumn shoots in the first and middle of December. Strong autumn shoots can enhance the nutrient accumulation of trees, thus effectively resisting the cold current.

two。 Do a good job of clearing the garden and painting the trunk white in winter. (1) removal of withered branches and diseased leaves: after autumn shoots were ripe, the Shiliu mixture of 0.9-1.2 Baume was sprayed to control overwintering diseases and pests. (2) White trunk: using quicklime 10 kg, sulfur powder 1 kg, adding water 30-40 kg, stirring evenly, adjusting to paste, painting trunk and primary and secondary branches, can effectively reduce freezing injury.

3. Tree plate bacon. Combined with the deep ploughing of the garden in winter, the 100 cm diameter of the tree plate is covered with pond mud, turf and so on. The height reaches 10 cm above the trunk grafting interface, which can effectively protect the grafting interface.

4. Covered with straw and bound. The main results are as follows: (1) within 120 cm diameter around the tree plate in winter, the soil temperature can be increased by covering 10 cm to 15 cm thick with straw, orange stalk, rape stalk, etc., or with plastic film. (2) Rice straw is used to bind the trunk and the first and second branches to keep the tree warm.

5. The orchard is watered. Before cooling, water is diverted into the orchard and irrigated throughout the orchard. If there is no irrigation condition, the tree plate is drenched with water. The adult tree is drenched with 100kg to 120kg of water per tree, which can replenish the water of the tree, increase the soil and air humidity, raise the temperature and reduce the freezing injury.

6. Smoke in the orchard. Before the cold snap comes, the orchard prepares combustible smoke such as husks, sawdust and turf, and puts it in a pile every 10 meters, mixed with a small amount of waste diesel oil, which can increase the heat of the smoke. After 22: 00:00 in the night when the cold snap comes, light the smoke and heat it up with smoke to keep warm and prevent frost.

7. Spray water to prevent freezing. In case of wet freezing, you should quickly organize manpower, shake off the ice from the tree and spray water to thaw.