NPK fertilizer is a complex, solid, compound, granular, nitrogen-phosphorus-potassium fertilizer. It contains phosphorus in a completely water-soluble form. It is used during the seedtime (basic) and before the seedtime (additional) application as well as for feeding regardless of soil types.
Physical and chemical properties
NPK fertilizer contains three active ingredients: nitrogen, phosphorus and potassium. The content of nitrogen, phosphorus and potassium is approximately equal, and water-soluble phosphates are more than 90%.
Mass fraction of trace elements and percentage of water depend on the brand of the fertilizer. Thus, mealiness has to be always equal to 100%.
Application in agriculture
NPK fertilizer is used for foliar feeding under grain, potatoes, sugar beets and other crops. As a fully water-soluble fertilizer it can be used in fertigation.
Terms and application rates of the NPK fertilizer are determined by the rules of applying it (instruction).
The behavior in soil
In the soil NPK fertilizer dissociates into different ions: nitrate ion NO3-, ammonium ion – NH4 +, phosphate ions – H2PO4-, HPO42- and PO43-.
In the growing season nitrate ion is biologically absorbed by plants and soil micro flora; it can also form the salts of alkali and alkaline earth metals in the soil solution. The salts of alkali and alkaline earth metals cause temporary acidification of the soil solution on acid soils. In gray soils and black soils the acidification is not observed. In cold season in the absence of the biological absorption the nitrate ion is easily washed out of the soil. This process occurs especially quickly with excessive moisture. In addition nitrate compounds of soil are inclined to the processes of the denitrification with the release of nitrogen in the gaseous state, which leads to some of its losses.
Ammonium Ion mainly is adsorbed by the soil colloids, leading to the formation of ammonium salts, which are then oxidized to nitrates.
Phosphate – ions slowly develop into different phosphorus compounds specific to a particular type of soil. This process takes place gradually and in various ways (colloid – chemical or chemical). The salts of orthophosphoric acid represent the greatest interest because plants and soil micro flora absorb them in a biological way.
The use of NPK fertilizer on different types of soils
NPK fertilizer is used on all types of soils.
– Sod podzolic soil. Adding this fertilizer ensures maximum efficiency in forest-meadow, steppe areas, in crops of sugar beet, cereals, potatoes and flax. High positive effect is observed when it is used in spring compared to autumn. In winter crops the dose of the fertilizer is divided equally between autumn and spring application.
In zones with sufficient moisture, especially on light structure soils, it is recommended to use compound fertilizers with lower nitrogen content (1: 2: 2, 1: 2: 1, 1: 4: 0) in autumn followed by applying additional nitrogen in order to reach optimal content of nitrogen in spring.
– Black soils, leached and sod podzolic clay soils. One-time introduction of all fertilizer doses is equal in its efficiency to fractional inclusion.
– Ordinary black soils, calcareous and south soils. The efficiency of the fertilizer is lower than in a wet forest-meadow area.
– Chestnut soils and grey soils. With the irrigation the efficiency of the fertilizer is significantly increased, especially in cereals, cotton and corn crops.
Impact on agricultural crops
When applying the fertilizer in the soil an increase in the yield of crops is observed; it is due to uniform distribution of nutrients and increase in their positional availability.
The presence of several ions leads to their combined effect on the plant and their combined effect is much more efficient than the influence of each ion separately. And it adds to a better use nutrients by plants.
Cereals, corn and cotton – the efficiency of NPK fertilizer is higher than mix of simple fertilizers, especially on chestnut and grey soils in terms of irrigated agriculture.
Technical and silo cultures as well as annual grasses respond well to all methods of applying this fertilizer.
Variants of packaging: bag of 50 kg., Big-Beg 1000 kg., Big-Beg 900 kg.