In recent years, through trial and practice, Hebei has developed a complete set of pollution-free standardized cultivation techniques for early spring dew. According to the Ministry of Agriculture, Hebei Provincial Technical Supervision Bureau and other industries or localities, GB/T8321, GB16715.5, NY/T5010, DB13/ T453 and other requirements related to the production of pollution-free vegetables, formulated the "Technical Regulations for Cultivation of Non-polluted Seedling Type Chinese Cabbage in Early Spring and Open Field", which was approved by Shijiazhuang Quality and Technical Supervision Bureau as the local standard of Shijiazhuang City, and promulgated and implemented to make Shijiazhuang suburban seedlings Provide theoretical basis for the healthy and safe production of Chinese cabbage. 1 variety selection In the early spring, the cultivation in the open field is in the low temperature period. In the selection of varieties, the varieties with good cold resistance, disease resistance, high quality and fast growth rate are selected, such as speed green, stone green rookie, and four seasons fast green. 2 Soil preparation and sowing 2.1 Site preparation Deeply sun-dried before winter, apply 1 500 ~ 2 000 kg of decomposed organic fertilizer, 10 ~ 12 kg of diammonium phosphate and 10 ~ 12 kg of potassium sulfate per acre. After the soil is thawed, the soil is started to be cultivated. It is usually planted in a flat area with a length of 6 to 8 m and a width of 1 to 1.5 m. 2.2 sowing The sowing date depends on the ground temperature. When the ground temperature of 10 cm is stable above 10 °C, the seeding rate is 400-500 g per mu. Live broadcast, broadcast or broadcast. The bottom water is poured before sowing, and the row spacing is 15 cm. The spreading can be mixed with the same amount of fine sand or corn mash and then broadcast. After sowing, the soil is covered by 0.5 cm, covered by a sunshade net or a mulch film. When 80% of the seeds are germinated and unearthed, the shading net or the mulch film is removed in time. 3 Field management 3.1 seedlings and seedlings After the true leaves are unfolded, the seedlings are separated, and the weeds are removed at the same time. 2~3 pieces of true leaves, the first time seedlings, plant spacing 2 ~ 3 cm; 3 ~ 4 pieces of true leaves when the seedlings, plant spacing 3 ~ 4 cm. 3.2 Fertilizer management After the seedlings are watered, the water will be poured once every 5 ~ 7 days, and 5 to 10 kg of urea will be applied per acre combined with watering, and the whole growth period will be applied 1 to 2 times. 4 Pest control 4.1 Agricultural control Reasonably arrange the mouthwash, avoid continuous cropping with cruciferous crops, select resistant varieties, increase organic fertilizer, clean the fields, and reduce the number of pests and diseases. 4.2 physical control Hang the yellow armyworm board 15 to 20 cm from the top of the plant to trap insects such as aphids and leaf miners, or use insecticidal lamps to trap insects. 4.3 Biological control In the adult stage of pests, suspension traps trap pests or use natural enemies to kill insects, and use pepper extracts for spraying during the larval stage of pests. 4.4 Chemical control In early spring, there are fewer pests and diseases in the open field, and the main pests are downy mildew, aphids and leaf miners. Downy mildew can be selected with 75% chlorothalonil WP 600 times solution, or 58% metalaxyl manganese zinc wettable powder 500 times solution, foliar spray. The aphids may be sprayed with 10% imidacloprid 1 000 times solution, or 40% acetamiprid water dispersing agent 1 000 ~ 2 000 times solution, or 50% anti-converse WP 2 000 times solution. The leaf miner can be sprayed with 20% avidin 1 500 times solution or 1% emamectin benzoate cream 2 000 ~ 3 000 times solution. In the selection of pharmaceuticals, low-toxic pesticides and biological pesticides must be used according to the requirements of pollution-free vegetable production. It is strictly forbidden to use high-toxic and high-residue pesticides to avoid excessive pesticide residues and affect the quality of vegetables. 5 harvesting In the spring, the open field is planted for about 40 days. After the plant reaches 8 leaves, it is harvested according to the market conditions. When harvesting, the plant is cut and the package is listed. The above content comes from the Science and Technology Support Project of Hebei Province. Farmers who have planted Chinese cabbage can learn more! Guangzhou Zhongzhinan Supply Chain Co.,Ltd. , https://www.gzzhongzhinan.com
