1、 Winter method

1. Pouring and sealing frozen water: the temperature in winter in the north is low, so it is necessary to bury soil in winter to avoid frostbite. In the first 10 days of soil burial, water the frozen water first, thoroughly and fully, so that the soil is in a saturated state, and then cover the soil when the soil is slightly dry

2. The first time to bury soil: after cooling, it is necessary to trim in time to avoid a large amount of evaporation of water. After pruning, bind all its branches and vines. When the temperature is two degrees in a row, bury the soil for the first time. At this time, the soil does not need to be too thick to cover the branches and vines

3. Second burial: when the temperature is continuously at 0 ℃, the second burial shall be carried out. At this time, the thickness of the buried soil should be increased, and an appropriate amount of hay should be prepared and paved near the root, so as to increase the temperature and avoid freezing the root. At this time, the thickness of the buried soil should be more than 60cm and the width should be about 1.8-2m, so as to ensure that it will not be frostbitten

2、 Winter precautions

During the winter, we should pay attention to its root system, so we must not expose the root system, otherwise it is easy to be frostbitten. When burying the soil for the second time, do not dig the soil near the root system, otherwise it is easy to enter the cold air. Dig and cover from a place far away from the root system. In addition, when burying the soil, the soil surface shall be flat and tightly buried. In the later stage, it shall be checked frequently and the loopholes found shall be repaired in time