How to use urea topdressing to get the highest utilization rate?

Urea is a kind of neutral fertilizer, which is used in all kinds of soil and crops. it is easy to preserve, easy to use and has little damage to the soil. Urea is a kind of fertilizer which is rich in nitrogen at present, but there are still a lot of points to pay attention to when using it. So, when using urea topdressing, how to use urea topdressing has the highest utilization rate?

I. the best use of urea

1. According to the soil

If the soil is fertile or barren, the amount of fertilizer used will of course be different. For example, the soil itself is very good, and if the plants planted on it grow well, then urea does not need to be used too much. If the soil is relatively barren and the crop yield is not high, the amount of urea can be slightly more.

two。 Look at crop demand

If you want to continue to use urea, the utilization rate is even higher, the most important thing is to understand the needs of crops. In her specific periods, the demand for nutrients will be very large, and if applied at this time, it can be better absorbed.

3. Dig ditches and apply fertilizer

There is a lot of nitrogen in urea. If it is directly sprinkled on the surface, most of it will be volatilized in four or five days, which is very wasteful. Especially when used in alkaline soil, the loss is even greater. So if you want to use urea, remember to dig ditches to fertilize, the depth of digging ditches should be at least less than 10 centimeters, so that the loss can be better reduced.

4. Don't touch the crops.

Urea is rich in nitrogen, the concentration is relatively high, and has a certain moisture absorption capacity, so do not use too close to the crops, otherwise it will burn out the seedlings and affect the growth of crops.

5. Use time

The use of urea does not mean that it can be absorbed by crops immediately, it has to go through a process of transformation. Therefore, it is estimated that when crops need a lot of nitrogen, urea should be applied a week in advance, so that it can be better used by crops.

6. You can't water it right away.

At the beginning, it is also mentioned that the use of urea has to go through a conversion process, in which it is best not to water, otherwise it will cause the loss of urea, usually after three to five days and then an appropriate amount of watering.

Matters needing attention in the application of urea

1. Deep application of urea and carrying fertilizer with water

In alkaline or alkaline soil, ammonium nitrogen is formed after urea hydrolysis, and surface application will cause ammonia volatilization, so the covering soil should be applied deeply. After urea was sprinkled on the surface of the paddy field, the ammonia volatilization after hydrolysis was 10%, 30%, and in alkaline soil, the nitrogen lost by ammonia volatilization was 12%, 60%. Under high temperature and high humidity, ammonia volatilization of urea can burn plants and accelerate nitrification rate, so it is very important to apply urea deeply and carry fertilizer with water.

Because urea can accumulate a large amount of ammonium ion in soil, which will increase pH by 2-3 units, and urea itself contains a certain amount of biuret, its concentration will inhibit the young roots and buds of crops at 500ppm, so urea is not easy to be used as seed fertilizer, seedling fertilizer and foliar fertilizer. The urea content in other application periods should not be too much or too concentrated. At the seedling stage, crops were damaged by biuret to form the disturbance of chlorophyll synthesis, and the leaves appeared green, yellowing and even albino patches or stripes.

two。 Urea should not be mixed with alkaline fertilizer.

Urea must be converted into ammonium nitrogen before it can be used by crops. under alkaline conditions, most of the nitrogen in ammonium nitrogen will be volatilized into ammonia, so urea can not be mixed with plant ash, calcium magnesium phosphate fertilizer, ammonium bicarbonate and other alkaline fertilizers.

Urea can be used not only in the application of base fertilizer, but also in the later stage of topdressing, which is very helpful to the growth of crops and has obvious effect. Master the above six points, increase the utilization rate of urea, let crops absorb well, high yield and high quantity is not a problem!