When is rape usually watered in spring? What are the main points of topdressing?

At present, rape is mainly used as an oil crop, and sometimes it is also used as animal feed. in addition, rape also has an ornamental price, and now many places have rape tourism culture. Rape is planted all over the world, and the requirements for planting conditions are not very high. When is it usually watered during rape planting in spring? What are the main points of topdressing?

When is rape usually watered in spring?

Rational irrigation and drainage is an important measure to ensure high and stable yield of rape. Rape has a long growth period, large nutrition, luxuriant leaves, many fruiting organs, and a large amount of water in its lifetime. Rape producing areas generally have less rainfall in autumn, winter and spring, and the soil is dry, which is not conducive to sowing seedlings and cultivating strong seedlings. The winter drought in the northern region often aggravates the frost injury and causes dead seedlings. There were more Rain Water in the southern region in the later period, resulting in waterlogging or waterlogging damage. Therefore, according to the characteristics of water demand of rape, irrigation and drainage should be carried out in time according to local conditions.

Second, what are the main points of topdressing rape in spring?

1. Early application of seedling fertilizer

Early application, frequent application of seedling fertilizer, timely supply of rape seedling nutrients, the use of a short period of higher temperature before winter to promote the growth of rape, achieve strong seedlings to survive the winter, and lay a foundation for high and stable yield of rape. Seedling fertilizer can be divided into early seedling stage and late seedling stage. The fertilizer in the early stage of seedling is applied when the seedling is fixed or 5 true leaves, generally applying 5-6 kg urea per mu, in the soil lacking phosphorus and potassium, if the base fertilizer is not applied phosphorus and potassium fertilizer, phosphorus and potassium fertilizer should be applied; topdressing in the later stage of seedling should depend on seedling condition and climate. Generally, 8-10 kg of high nitrogen compound fertilizer is applied per mu. The varieties with strong spring or the warmer areas in winter should be applied early, and the low temperature in winter or triple-cropping rape should be applied late.

2. Steady application of bolting fertilizer

The bolting stage of rape is the period of vegetative growth and reproductive growth, with rapid bolting, long branches, increased leaf area and large differentiation of flower buds, which is not only the most fertilizer period, but also the key period of increasing branches and pods. Therefore, bolting fertilizer should be applied steadily according to the application and growth of base fertilizer and seedling fertilizer. Basal and seedling fertilizer is sufficient, plant growth is robust, and bolting fertilizer can be applied little or not; if basal and seedling fertilizer is insufficient, bolting fertilizer should be applied early if there is a tendency to de-fertilize. Generally, 15-20 kg of high nitrogen compound fertilizer is applied per mu. Fertilization time is generally in the middle of bolting, bolting height of 15-30 cm is better. But those with weak growth can be fertilized at the initial stage of bolting to avoid premature senility; those with strong growth can be applied at the later stage of bolting, when the bolting height is 30-50 cm, so as not to cause canopy caused by excessive growth during flowering.

3. Skillfully apply flower fertilizer

Rape blossoms and pods after bolting, and the number and weight of seeds are closely related to the nutritional conditions after flowering. For vigorous growth, large amount of fertilizer can not be applied or less applied at bolting stage; no fertilizer is applied to early-maturing varieties, or less at the initial flowering stage; topdressing at flowering stage can be foliar spraying, and 0.1-0.2% urea or 0.2% potassium dihydrogen phosphate is sprayed at flowering and podding stage. In addition, 0.2% borax aqueous solution can be sprayed once in the late seedling stage and bolting stage to prevent the phenomenon of "flowering but unfruitful" and increase the yield.