1. When will Chinese cabbage be planted and harvested?
1. Planting
Seedling raising in greenhouse is slower in March than in1late October, and in May than in early February to late March.
harvest
The harvest in open field in March is slower than that in late February to late March, the harvest in greenhouse in April is slower than that in late March to early April, and the harvest in May is slower than that in late April to early May. Remove the roots with a kitchen knife and clean vegetables will be on the market.
Second, how to scientifically fertilize Chinese cabbage?
In vegetable production, for many vegetable farmers, the blind application of nitrogen and phosphorus fertilizer in Chinese cabbage production is serious, the ratio of nitrogen, phosphorus and potassium is unreasonable, the blind application of high-phosphorus compound fertilizer, the insufficient amount of organic fertilizer and the serious acidification of vegetable soil. So pay attention to the following points when fertilizing:
1. Fertilization principle
According to soil fertility conditions and target yield, optimize the amount of nitrogen, phosphorus and potassium fertilizer; Base fertilizer is the main fertilizer, and base fertilizer and topdressing are combined; Topdressing is mainly based on nitrogen fertilizer, nitrogen, phosphorus and potassium fertilizer are reasonably matched, and trace elements are appropriately supplemented. Strengthen water and fertilizer management after planting, and stop applying nitrogen fertilizer one week before harvest; The content of available molybdenum and other trace elements in high acid soil in south China is low, so attention should be paid to the supplement of trace elements; When vegetables are seriously acidified, lime or soil conditioner should be applied appropriately. Advocate the application of decomposed farm manure or commercial organic fertilizer to loosen soil, improve soil fertility and promote vegetable growth.
2. Fertilization amount
The yield of Chinese cabbage per mu is 2500-3000kg, and each mu is applied with decomposed farm manure 1 000- 1 500kg or commercial organic fertilizer 200kg, urea1.5-1.7kg (converted into pure N7-8kg) and calcium.
3. Fertilization method
Chinese cabbage has a short growth period. Sufficient base fertilizer must be applied before planting. All organic fertilizer, phosphate fertilizer, potash fertilizer and 20% nitrogen fertilizer should be applied in strips or as base fertilizer. Topdressing should generally be applied 5 days after sowing or after seedling age 15 in the direct seeding site, once every 5-7 days, and twice in the whole growth period, with 30% nitrogen fertilizer for the first time and 50% nitrogen fertilizer for the second time.
For plots with soil pH less than 5, 50- 100 kg of quicklime or 50- 100 kg of soil conditioner can be applied one week before planting, which can improve soil pH and supplement calcium. When the symptoms of molybdenum deficiency appear in the middle and late growth period of vegetables, spray 0.02%-0. 1% ammonium molybdate aqueous solution (or mixed pesticides) on the leaves every 5-6 days 1 time, twice in a row.
Chinese cabbage is vulnerable to pests such as Pieris rapae, Pieris rapae, aphids, etc. In the growth period, vegetable farmers had better spray chemicals in advance to control it, and at the same time, weed and litter in the field should be removed in time to avoid pests.