In early winter, after the leaves of winter jujube fall, the garden should be cleaned once, and the dead leaves and weeds can be burned off with fire.

Second, reasonable scraping and whitening

During dormancy, you can scrape the skin and whitewash it. Young trees are generally whitewashed only before the trunk forms rough skin, so you don't have to scrape it. The trunk and branches of adult trees form a layer of rough skin every year, and the skin should be scraped.

White coating can reduce the frostbite of jujube trees and prevent the harm of leafhoppers and germs. Preparation method of white coat agent: water 10, quicklime 3, sulfur mixture stock solution 0.5, salt 0.5 and a little oil (animal or vegetable oil).

With the growth of tree age, the bark becomes thicker and lacks ductility, which hinders the thick growth of trunk and makes the tree prone to premature aging. At the same time, cracks in bark are wintering places for many diseases and insect pests. Therefore, timely scraping off old bark and centralized burning can not only promote the growth of trees, but also prevent and control pests and diseases, killing two birds with one stone.

Scraping is generally carried out with a special scraper. It is required to scrape the rough and cracked cortex of the old bark to a certain extent, and it is not allowed to scratch the tender bark and xylem too deeply. When scraping the skin, put a newspaper or plastic cloth under the tree first, and the scraped bark must be cleaned up in time and burned centrally.

Third, heal scars and repair tree holes.

When logging in winter, it often leads to big sawing, and the tree is strong and the wound heals quickly, so it is generally not easy to go wrong. The tree is weak, because the wound area is too large and the healing time is long, it is easy to cause the wound to rot and affect the growth and life of the tree. Therefore, the wound should be protected. First, cut the kerf flat with a knife or scissors to make the cortex edge arc, then disinfect the wound with 2% copper sulfate or 5 baume stone sulfur mixture, and finally apply a protective agent to prevent the wound from rotting and promote the wound healing. Tung oil, lead oil, waxing etc. Used as a protective agent. The formula of wax oil is rosin 800g, grease 100g, alcohol 300g and turpentine 500g. The easiest way is to apply asphalt paint to the big wound.

Treatment of disease scar If there is a disease scar on the trunk, it is necessary to scrape off the disease skin with a knife to expose healthy tissue, then smooth the edge of the scratch with a knife, apply drugs such as hydrogen peroxide on the disease spot, and then wrap it with mud to promote its healing.

Repair of Tree Holes Jujube trees often have a "broken belly" phenomenon, or tree holes are caused by other reasons. When this situation is found, jujube farmers should fill it in time to prevent the tree hole from expanding. The method of filling the hole is to clean up the rotten wood in the hole, scrape off the dead tissue at the edge of the hole, then disinfect it and fill the hole with chemicals. The filler is preferably a mixture of cement and pebbles (1: 3). Small holes can also be filled with wooden wedges nailed in tree holes, which can protect wounds or accelerate healing.

Fourth, scientific fertilization.

If there is no fertilization in the protected winter jujube orchard in autumn, it is necessary to seize the winter fertilization season, apply the fertilizer well and fully, and lay a good nutritional foundation for cultivating soil, raising roots and strengthening trees in the coming year. Fertilization varieties should be mainly organic fertilizer or flocking refined organic fertilizer, with compound fertilizer, silicon-calcium-magnesium-potassium fertilizer and biological fertilizer. The amount of fertilization can be carried out according to the autumn fertilization plan, and it can also be reasonably applied in combination with the strength of the tree to provide enough nutrition for the healthy growth of jujube trees in the coming year.

Five, plastic pruning

Plastic pruning is to set up a shelf and build a fruit skeleton for winter jujube. When the shelf is set up, the fruit can be better and the yield can be increased more. The function of pruning is to cultivate the tree shape, balance the tree potential, adjust the relationship between vegetative growth and reproductive growth, adjust the growth and nutrient distribution of indoor branches, improve the ventilation and light transmission conditions in the crown, promote the tree potential and moderate fruit, and thus obtain higher economic benefits.

Sixth, don't buckle the shed too early.

In the eastern part of Guanzhong, the suitable time to buckle the shed is mid-February, which is easily affected by snow and wind disasters. At the same time, the lack of dormancy of winter jujube affects flower bud differentiation and jujube hangs buds. When the lowest temperature is not lower than -2 degrees, the buckle shed is the most suitable. For the greenhouse with heat preservation equipment, the time to buckle the shed should be 10~ 15 days in advance. Before the tent is buckled, it is necessary to know the long-term weather through the meteorological department. If the cold air activity is frequent, it is easy to have "early spring cold" weather, and the tent can be postponed for 7~ 10 days.