Information for farmers

Application rate 30–300 kg/ha (of active material):

  • N = nitrogen (consumed in form of (NO3)— or (NH4)+ ions)
  • P = phosphorus (consumed in form of (H2PO4)-;
  • K = potassium (consumed in form of (K)+ ion.
    • Nitrogen is the main protein (building) element necessary for development of plants and animals.
    • It determines and speeds up the growth  of plants’ vegetative part
    • It is necessary for root system, stalk, foliage development, as well as to form the reproduction organs, seeds and fruits.
    • Nitrogen should be available to plants through the whole growing process
    • Lack of nitrogen reduces the output and the quality of the final product.
      • Protein and fat content decreases
      • Plants grow unhealthy and small
      • The volume of harvest decreases

    Crops that require higher doses of nitrogen:

    • All grain-crops
    • Corn
    • Fodder crops
    • Renewable meadows and pastures

    In fertilizers nitrogen is usually present in 2 forms – nitrate and ammonium.

    Ion formula

    Universal name

    Fertilizers that contain the ion

    Availability for plants



    Ammonium nitrate, ammonium nitrate limestone, urea and ammonium blend, nitrogen sulphate, complex fertilizers (based on ammonium nitrate)

    Immediate effect

    Easily travels through the soil

    Easily flammable



    Ammonia, ammonium sulphate, urea and ammonium blend, complex fertilizers (based om ammonium nitrate), nitrogen sulphate

    Available but has a more prolonged effect due to adsorption on soil particles, consequently becomes available and absorbed by plants



    Urea, urea and ammonia blend, complex fertilizers (based on urea)

    Unavailable to plants.

    However due to soil microorganisms activities NH2 restores to NH4. The reaction speed depends on the soil temperature (>+12)

    Doesn’t leach



    Calcium cyanamide

    Unavailable to plants CN2=>NH2=>NH4

    Restores due to the activities of microorganisms. The reaction speed depends on the soil temperature (>+12)?

    Doesn’t leach

    * Not in fact used in agriculture.

  • Supplies any reactions (fission, fusion) inside cells with energy
    • improves nitrogen nutrition (a plant spends 2 phosphorus molecules to to assimilate nitrogen from NO3);
    • supplies energy for seed germination;
    • secures rapid growth and development of root system;
    • accelerates ripening;
    • is necessary for reproduction.
  • Forms the new harvest:
    • The volume of the future harvest (amount of seeds) is determined during the first weeks of a seedling's development. If a plant doesn’t receive the necessary amount of phosphorus, it will form the number of seeds using the available nutrition only. This is the natural species maintenance: the plants tent to produce the least amount of seeds, which will however be strong and able to produce healthy seedlings. It is impossible to change the negative effect caused by the lack of phosphorus in any subsiquent stages of a seedling's development.
  • Improves the quality of the final product:
    • Increases the sugar and carotene content.

Crops that require higher doses of phosphorus fertilizers:

Vegetables, leguminous plants, roots.

Phosphorus travels very little through the soil and easily interacts with soil. particles generating new compounds and taking forms not available for plants. This is why the efficiency of phosphorus fertilizers does not usually exceed 15?22 %.

Plants assimilate phosphorus in form of (H2PO4) anion

According to the degree of availability for plants phosphorus fertilizers are differentiated as:

  • Water soluble phosphorus fertilizers:
    • Simple superphosphate
    • Triple superphosphate
  • Partly soluble in water and weak acids soluble:
    • superphosphate (23?26%  P2O5).
  • Soluble in weak acids:
    • dicalcium phosphate
    • precipitate
  • soluble in strong acids:
  • Very little available for plants, effective for use on humid and acid soils:
    • Phosphorite powder(30%  P2O5).

Potassium is responsible for the intensity of nutrients assimilation, increases the resistance to fungal diseases and dry weather, secures the effective assimilation of nitrogen and phosphorus, improves the quality of final agricultural production.

In plants potassium regulates the following functions:

  • Effectiveness of water consumption (turgor, resistance to dry weather);
  • Circulation of water and nutrients inside the plant (ripening);
  • Sugar transportation (accumulation of nutrients);
  • Protein synthesis;
  • Starch generation.

Crops sensitive to the lack of potassium:

  • Potato, white beet, carrot, sunflower, soy.

Kinds of potassium fertilizers:

Potassium chloride – 40-60% K2O:

  • Used for most crops on almost all soils;
  • Applied mostly in fall with major application.

Potassium sulphate – 50% K2O:

  • Applied in fall, in spring and before sowing;
  • For chlorine-sensitive crops (potato, buckwheat, essential oil plants, fruits and berries, vine).

Potassium metaphosphate and potassium nitrate

  • For fertilization in greenhouses and additional nutrition by irrigation.