Spring cabbage winter seedling 4 points

Spring cabbage is a kind of vegetable variety with large planting area in the middle and south of our province. Spring cabbage production has the characteristics of less investment, labor-saving, labor-saving and high yield. Now, it is the golden season of cabbage breeding in early spring. Below, introduce the main points of breeding techniques of spring cabbage for your reference: first, suitable varieties for open field planting in spring, such as Zhonggan 15, Zhonggan 21, Shuanghuan 15 and other varieties with good early maturity, high yield and strong disease resistance. Arch shed cultivation in early spring can choose varieties with strong cold tolerance, strong disease resistance and strong winter, such as Lvbaowang, Shuanghuan 45, Xuan 8398, Chunqiang and so on. Second, to prepare the nursery bed, the soil should be fertile. In the pastoral soil where cruciferous vegetables were not planted in the previous year, fully mature farm manure was applied and mixed with an appropriate amount of ternary compound fertilizer of nitrogen, phosphorus and potassium. To thoroughly disinfect the seedbed before sowing, 40% pentachloronitrobenzene and 50% thiram wettable powder can be used to mix 9 grams per square meter. After sowing, the soil is covered with 3 medicines. Before sowing, the seeds were mixed with 50% thiram of 0.3% seed weight and 65% mancozeb wettable powder. Third, sowing in North China at the right time, the suitable sowing time of open field cabbage and cold shed early spring cabbage is from late December to early and middle January, and most seedlings are raised in solar greenhouse or improved sunny border. Generally, the planting density of early-maturing varieties is about 4500 plants per mu, while that of mid-early-maturing varieties is 3500-4000 plants per mu, and the seed consumption per mu is about 50 grams. Before sowing, seeds generally do not need to sprout, dry seeds can be sown, seedling beds should be watered with sufficient bottom water, seeds should be sown evenly, and after sowing, they should be covered with sifted medicinal soil to preserve soil moisture and prevent seedling beds from cracking. 4. Nursery bed management before emergence, the temperature of greenhouse or sunny bed should be kept between 15-25 ℃. Generally, all seedlings can be produced after 5 days of sowing. At this time, attention should be paid to timely gradual ventilation to keep the temperature between 10-20 ℃. If the seedlings are too dense, it is necessary to carry out inter-seedlings to prevent seedlings from overgrowing. When the seedlings grow to 3 true leaves (about the first and middle days of February), the seedlings should be divided once, and the seedlings should be transplanted into a nutrition bowl. The temperature of the seedling separation bed is generally controlled at 8: 20 ℃. Before the seedlings are planted in March, the seedlings can be "refined" at low temperature, gradually increasing the air release rate, and the lowest temperature of the seedling bed can be gradually reduced to about 5 ℃.