Five measures to prevent freezing of Brassica napus by fertilization, soil cultivation, Irrigation, Grass picking and early bolting

First, cultivate the soil through ploughing. Before the soil is frozen, ploughing can loosen the soil and thicken the soil layer of rape root system, which is helpful to prevent the attack of cold wind and improve the ability of heat absorption, heat preservation and cold resistance. Especially the tall seedlings, after the cultivation of soil, the rhizome becomes shorter, which is beneficial to keep warm.

Anti-freezing guidance of rapeseed

Second, re-apply winter fertilizer. Before the arrival of severe cold, topdressing wax fertilizer and increasing phosphorus and potassium fertilizer can not only enhance the cold resistance of rape, but also supply the nutrition of rape during overwintering and bolting and flowering stage, and ensure the balanced growth of rape.

Third, cover against cold. Rape rows can be covered with rice straw, husk or other crop straw to reduce the attack of cold wind. Before the cold wave comes, sprinkle grain shell ash, plant ash, fire soil ash and so on on the rape leaves to prevent the leaves from freezing.

Fourth, irrigation and anti-freezing. Timely irrigation of rape fields before freezing or severe cold can avoid a sharp drop in ground temperature and alleviate freezing damage, especially to prevent dry freezing. At the same time, after irrigation, rape roots are closely combined with soil, which is beneficial for rape to absorb water and nutrients. After freezing, the ditch should be cleared in time to drain, so as not to hurt the root due to waterlogging.

Fifth, remove the early bolting. If rape appears the phenomenon of early bolting and early flowering, it will consume a lot of nutrients and weaken the cold resistance of rape. Bolting should be carried out at noon on a sunny day. After bolting, apply appropriate amount of available nitrogen fertilizer in time to promote the growth of rape and prevent the occurrence of freezing injury.