What are the precautions for applying urea? Mastering these points is key

1. It should not be mixed or applied together with alkaline fertilizers

Urea cannot be mixed or applied at the same time with alkaline fertilizers such as lime, plant ash, and calcium magnesium phosphate. Generally, in summer and autumn, urea and alkaline fertilizers should be applied 3 to 4 days apart, and in winter and spring they should be applied 7 to 8 days apart.

2. It should not be used as a seed-dressing fertilizer

During production, urea produces a small amount of biuret. When the biuret content exceeds 2%, it will poison seeds and seedlings, affecting seed germination and seedling growth.

3. It should not be irrigated immediately after application

If irrigation is done immediately after application, or if it is applied before heavy rain in dryland, urea will dissolve in water and be lost. Generally, in summer and autumn, irrigation should be done 2 to 3 days after application, and in winter and spring, irrigation should be done 7 to 8 days after application.

4. It should not be broadcast on the soil surface

At room temperature, urea needs 4 to 5 days to transform before it can be utilized. If broadcast on the soil surface, most of it volatilizes during ammonification, and the actual utilization rate is only about 30%. If broadcast on alkaline soil and soil with high organic matter content, nitrogen loss will be even faster. Deep application of urea, incorporating the fertilizer into the soil, keeps the fertilizer in a moist soil layer and helps give full play to its fertilizer efficiency.

5. It should not be applied too late

Applying urea too late is not conducive to giving full play to its fertilizer efficiency and can easily cause crops to remain green and mature late, so it should generally be applied 4 to 7 days earlier than other nitrogen fertilizers. Gao Huihui