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Fertilizer UAN: instructions for use and composition, dosage and analogues

Fertilizer UAN: instructions for use and composition, dosage and analogues

UAN fertilizers are carbamide-ammonia mixtures, which are often used in agricultural practice. In most cases, such funds are used to feed winter cereals. However, they can also process other varieties of crops. The substance is released in the form of a liquid concentrate. It needs to be mixed with water and applied root or foliar.

Composition and release form of the fertilizer

UAN fertilizers contain the following components:

  • 30% urea;
  • 40% s altpeter;
  • 30% water and corrosion inhibitors.

In total, 27-32% nitrogen is present in fertilizers. This component is presented in the preparation in the following forms:

  • nitrate - quickly absorbed by crops;
  • ammonium - after a certain time it is transformed into an assimilated form;
  • amide - first the substance passes into the ammonium, and then the nitrate form.

Because the use of UAN top dressing helps to achieve a lasting effect. Even when frozen, the solutions retain their agrochemical characteristics and remain stable with increasing temperatures. Therefore, specific storage conditions are not needed.

Use and effectiveness

From a chemical point of view, the drug is considered a solution of ammonium nitrate and urea, and the components are combined in optimal proportions.

UAN is primarily considered a nitrogen fertilizer that helps crops grow green mass.

At the same time, the properties of the drug are due to the components that are present in its composition:

  1. Nitrate nitrogen - actively absorbed by the root system. Thanks to this, crops are saturated with nutrients in a short time. This makes the application of top dressing more effective.
  2. Ammonium nitrogen - cannot be absorbed by plant elements. The action of this substance is based on the fact that it is perfectly preserved in the soil and is resistant to leaching. Therefore, the composition can be used in areas with a high level of groundwater and in areas with an increased amount of precipitation. Also, the presence of this component allows you to fertilize in the first spring months. At the same time, under the influence of temperature and the work of soil microorganisms, the composition is transformed into a nitrate form.
  3. Amid nitrogen - it is perfectly absorbed by the leaves of crops. However, for this, the substance must first take the ammonium, and then the nitrate form. Thanks to the multi-component reaction, it is possible to achieve a longer effect from the use of top dressing.

Instructions for using CAS

CAS can be used in 2 main ways:

  1. Root - in this case, the substance is distributed over the surface of the earth. Although it does not contain free form ammonia, in hot weather and in the absence of precipitation or watering, a small surface patching is necessary.
  2. Foliar - at the same time, foliage is irrigated. The procedure is performed during the growing season or during frosts, when the plant cannot receive nutrition by the root method. It is best to carry out the procedure in the morning or in the evening. Daytime work is permissible only in cloudy cool weather.

The application rate of a substance depends on many factors. This is influenced by the type of plant, the processing period, the method of applying the drug, climatic conditions. For cereal crops, triple irrigation tactics are suitable:

  1. In the spring, after the snow melts. In this case, the temperature should be no more than +10 degrees. For 1 hectare it is required to use 30-40 kilograms of fertilizer. It does not need to be diluted.
  2. Late spring or summer, at the stage of head shooting. The composition can be combined with trace elements, growth stimulants, pesticides. For 1 hectare it is worth using 30 kilograms of the active substance. It must be mixed with water in a ratio of 1:2. With the simultaneous use of a herbicide, a ratio of 1:3 or 1:4 is used.
  3. In autumn, at the initial stage of heading. Winter crops need to be fed at the rate of 10 kilograms of the drug per 1 hectare.


The tool needs to follow a number of recommendations for storage and transportation. Spraying UAN is required using special equipment.

If you violate the rules for using fertilizer, there is a risk of burns on the shoots.

Compatible with what?

The product can be combined with pesticides, growth stimulants and trace elements. This will help to enrich the soil with nutrients and protect plants from pests.

Storage and transportation

KAS is required to be stored in special tanks. The composition is considered flammable and explosive. At the same time, it is characterized by a low crystallization temperature and freezing at -26 degrees. Due to this, it is possible to transport and store top dressing for a whole year. Crystal formation and temporary freezing of the substance are not dangerous.


The analogues of the product include "Plantafol" and nitrogen-phosphorus fertilizer NP.

UAN fertilizers are considered effective means that help to saturate the soil with nitrogen and stimulate the growth of green mass of plants. At the same time, it is important to apply top dressing correctly.

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