Overall Management of rosette stage of Chinese Cabbage

Chinese cabbage, biennial herb, 40-60 cm tall, often glabrous throughout, sometimes with a few bristles on the midrib below the leaves. Native to northern China, it is a leafy vegetable of Brassica in the cruciferous family, usually referring to Chinese cabbage; it also includes Chinese cabbage and cabbage, namely "cabbage" or "cabbage", a cultivated variety of cabbage. It is introduced to the south and cultivated in all parts of the north and south. It was introduced into Japan, Europe and the United States in the 19th century. There are many kinds of cabbages. The northern cabbages include Jiaozhou cabbage in Shandong province, Beijing green white cabbage, green Tianjin Chinese cabbage, northeast dwarf cabbage, Yutian cabbage, and Dabian cabbage in Yangcheng, Shanxi. Cabbage is eaten with tender leaf balls, rosette leaves or flower stems. The cultivated area and consumption rank first among all kinds of vegetables in China.

The cultivation season of Chinese cabbage

Early-maturing varieties are generally sown in the first and middle of August, and some are sown earlier in late July. Medium-maturing varieties can be sown from late August to early September. Late-maturing varieties should be sowed in late August.

The management of the rosette stage of Chinese cabbage is very important for the production of Chinese cabbage, so how to manage the rosette stage of Chinese cabbage comprehensively?

The rosette stage is the key period for the growth of Chinese cabbage, when the growth rate is fast, the root system and leaves grow vigorously, but it is also the key period for the occurrence of diseases. In management, it is necessary to promote the rapid growth of leaves, form the maximum leaf assimilation area as soon as possible, promote the rapid development of roots, control the growth of leaves in the later stage, and prevent the occurrence of diseases.

Fertilizer and water management. In the rosette stage of Chinese cabbage, the growth rate and growth are very fast, and the amount of fertilizer required is increased. In the initial stage of the rosette, we should apply "hair" fertilizer, applying urea 8-10 kg per mu, the method is to open 10 cm ditch on one side of the ridge, fertilize and close the ditch and water it, and pay attention to less root damage when opening the ditch. The water demand during the heading period is large, so it should be fully irrigated in combination with topdressing, usually once every 7 days, to keep the ground moist frequently. Stop watering 10 days before harvest, usually once every 7 days, to keep the ground moist. Stop watering 10 days before harvest.

Squatting seedlings to promote roots. Chinese cabbage can control watering to squat seedlings from mid-rosette to heading stage, control vigorous growth, thicken leaves, promote root development, help nutrient accumulation, reduce field humidity, and control the occurrence and development of diseases. The squatting time varied from 10 to 20 days, and the leaf color changed from green to yellow or wilted slightly at noon. There are less squatting seedlings in the following situations: varieties with short growth period and fast growth, sowing too late, transplanting large seedlings, poor seedling condition, drought, less rain, higher temperature and lack of water, fertilizer and sand.

Pest control. The main diseases in rosette stage of Chinese cabbage were downy mildew and soft rot. Prevention and control methods: first, to control humidity to prevent downy mildew and soft rot. The second is to find the disease, timely use of drugs to control the development of the disease.