When is crop topdressing effective?

When is the effect of topdressing crops good? Please give the following introduction to some of the best topdressing periods for crops: under the principle of balanced fertilization, the peak period of nutrition absorption is from post-jointing to trumpet mouth stage of corn, and the first topdressing can be made before and after jointing. 10 kg urea per mu and 20 kg urea per mu after topdressing the second fertilizer 10 days before heading bear ear. If the base fertilizer and seed fertilizer are sufficient, and the soil is very fertile, one time topdressing can be concentrated, combined with the second weeding for deep fertilization. The absorption of nitrogen fertilizer by rice in the best topdressing period began to increase gradually after turning green. In order to promote early emergence and early tillering of rice, tillering fertilizer should be applied and re-applied early. Generally, 10 kg of urea per mu can be applied 10 days after transplanting, and 15 kg of urea can be applied at heading. In order to meet the nutrient needs of sorghum from jointing to heading stage, the best topdressing stage of sorghum should be topdressing the first fertilizer at jointing stage, applying urea 8 kg / mu, and applying urea 10 kg / mu at the flag booting stage. The nutritional critical period of peanut in the best topdressing period of peanut is in the early growth stage. about 15 days after emergence, flower buds begin to differentiate and root nodules begin to form. When two pairs of lateral branches appear in the plant, nitrogen fertilizer should be applied once in time, and urea 5 kg per mu should be applied. The combination of soil cultivation and spraying multi-element fertilizer after flowering is beneficial to reduce the empty fruit rate and increase the yield of peanut. Soybean in the best topdressing period is a crop that needs more nitrogen, but it has rhizobium nitrogen fixation which can solve part of the nitrogen source. However, during the growth period, topdressing should be applied by stages, and nitrogen fertilizer should be applied once in the early flowering stage of soybean. Generally, urea can be applied at a rate of 8kg / mu. In the podding stage of soybean, the effect of increasing yield was more obvious when the weak foliar was sprayed with multi-element fertilizer. Click to get more compound fertilizer application techniques