UAN is a mixture of aqueous solutions of ammonium nitrate and carbamide (in the ratio of 35.4% of carbamide, 44.3% of niter, 19.4% of water, 0.5% of ammonia water). Density of liquid fertilizer to 1.34 kg/m3.
Thus, the application of UAN provides prolonged nutrition of plants with nitrogen. In view of the lack of free ammonia in the UAN, it does not evaporate into the atmosphere when applied, but the presence of an ammonium form still makes the minimum embedding desirable, especially under high-temperature conditions and without precipitation after application.
One of the most important advantages of UAN is its high adaptability:
When using liquid fertilizers, it is easier to maintain a constant level of processing.
The application of UAN is well combined with the use of pesticides in one tank mix, which reduces the number of operations for the care of crops.
It is advisable to use for fractional fertilizing of vegetative plants. At the same time, both root and foliar top feeding take place. Depending on the phases of development of cultivated plants and the equipment used, UAN is diluted with water in the required ratio.
The application of UAN is well combined with microelements.
The norms and doses of UAN application depend on the type of culture, the time and method of introduction, the predecessor and other factors. There are no special restrictions.
UAN solutions can be used without diluting and with diluting by water. It depends on the technical capabilities of the units. When diluting, the working solution consumption per 1 hectare should be 100-300 liters.
Any sprayer can be converted to applicate the UAN, but this requires:
replace parts from non-ferrous metals with PVC, stainless, or fiberglass;
To carry out foliar feeding, replace the spray nozzles of the sprayers with nozzles that create several jets (streams) that are the same from 3 to 7.
The size of the droplets sprayed with sprayers when applying plant protection products (herbicides, fungicides) does not exceed 0.3 mm. This is done to ensure that the drops fall on pests and stay on the leaves, thereby protecting them from phytophages. But with the feeding of pure UAN it is necessary to achieve such a drop size that the substance slides off the plant, only by moistening the sheet. Otherwise, it may get burnt. And the nozzles creating continuous streams just give the required large-droplet solution. Slotted nozzles can be used only when applied with herbicides with mandatory dilution of UAN with water;
To work in windy weather, use extension hoses.
In recent years, self-propelled sprayers «Rosa» and «Vodoley» have been very popular among farmers. First one is a production of the Belarusian company, second was released in Ukraine.
Unfortunately, this result can not be shown by standard sprayers, which led to the success of self-propelled sprayers «Vodoley» и «Rosa».
