Matters needing attention in urea application

1. It is not suitable to be mixed or applied with alkaline fertilizer.

Urea can not be mixed with lime, plant ash, calcium magnesium phosphate fertilizer and other alkaline fertilizers or applied at the same time. Generally speaking, urea and alkaline fertilizer should be staggered for 3-4 days in summer and autumn, and 7-8 days in winter and spring.

Second, it is not suitable to be mixed with seed fertilizer

Urea produces a small amount of biuret in the production process, and when the biuret content is more than 2%, it will be toxic to seeds and seedlings, affecting seed germination and seedling growth.

Third, irrigation immediately after it is not suitable for application

If irrigation is applied immediately after application or dry land is applied before heavy rain, urea will dissolve in the water and lose. In general, irrigation should be done 2-3 days after application in summer and autumn, and 7-8 days after application in winter and spring.

Fourth, it is not suitable to spread on the surface.

It takes 4-5 days to convert urea at room temperature before it can be used. If sprinkled on the surface, most of it will be volatilized in the ammoniation process, and the actual utilization rate is only about 30%. If spread in alkaline soil and soil with high content of organic matter, nitrogen loss will be faster. The deep application of urea will melt fertilizer into the soil and make the fertilizer in the wet soil layer, which is beneficial to the exertion of fertilizer effect.

5. It should not be applied too late

Applying urea too late is not conducive to the exertion of fertilizer effect, and it is easy to cause crops to be green and mature late, so it should be applied 4-7 days earlier than other nitrogen fertilizers. Gao Huihui