2. Burying method: Choose an open ground with flat and dry terrain, sticky land, low groundwater level, good drainage and convenient transportation to dig a water storage ditch. The depth depends on the thickness of the local frozen soil layer and whether it is stored for winter. Generally, the width of the ditch is 1.7 m and the depth is about 1.5-2 m, which is the best in the east-west direction. The excavated soil was made into ridges around the ditch.
3. Lay a layer of straw or vegetable leaves at the bottom of the ditch. After pulling up the Chinese cabbage, dry it for 3-5 days. When it gets cold, pile the vegetable roots in. Choose a cold day when the temperature drops to about 0℃, and put the Chinese cabbage into the ditch while it is cold. When planting vegetables, put the roots of vegetable trees down so that the heads of vegetables on them are even.
4. After the Chinese cabbage enters the ditch, cover it with a layer of grass or cover it with 2-3 cm of soil. Later, as the temperature drops, the frozen soil layer deepens and can be covered for 2-3 times. Cover the soil for the last time, so that the total thickness of the covered soil is equivalent to the local frozen soil layer.
5. Check carefully every time you cover the soil. If the temperature in the ditch is too high or there are rotten vegetables, water the vegetables in time to eliminate rotten, sick and yellow leaves.
6. Pit storage method: Chinese cabbage is harvested and sent to the vicinity of the vegetable pit. The yard is in the leeward and sunny place, and it is pre-stored for 10-20 days. When the outside temperature is about -3℃, enter the cellar in time. Before entering the cellar, remove the root soil and rotten leaves. The bottom of the cellar should be covered with 60mm sand and a layer of straw. There is a 50 cm passage in the middle of the cellar, with vegetables piled up on both sides. The width of vegetables is 90 cm, the height is 2.5 m, and the distance from the cellar wall is 10 cm.
7. Before entering the cellar, water the vegetables every 3 days to prevent the temperature from being too high. Turn the vegetables layer by layer, clean up the rotten leaves and take off the help. With the decrease of external temperature, the pouring cycle should be extended and the pit mouth should be sealed to keep the temperature in the pit.