Large amount of humified organic carbon (humic and fulvic carbon)


NPK (MgO) 5-12-12 (2)

with  Zinc (Zn)


It is an NPK organo-mineral fertilizer with magnesium and zinc, particularly suitable on extensive crops such as wheat, corn, sugar beet, in soils with low potassium level; it is advised to meet the increased needs of phosphorus and potassium required by young plants nursery : vineyard, fruit trees, citrus, etc.


• Packaging: 500 kg

• Shape: minipellets

• NPK ratio: 1 : 2,4 : 2,4

It speeds up the responsiveness of roots and crops starting in the early stages of the growing period.
SIAPOR CHALLENGE, with POTASSIUM CHLORIDE, should be used on any crops  less sensitive to salinity, preferably checked through analytical controls.
NPK, Mg and Zn nutritive units, while reacting with the humified organic matter  (humic and fulvic acids and humins), acquire a considerable degree of protection thus allowing an optimal agronomic yield.

This allows:

  • high and extended nutrient availability for the entire crop cycle;
  • reduction of losses due to insolubility, leaching and evaporation;
  • flexibility of the fertilizing cycle with the option of  applying it before the normal period of nutritional use;
  • saving of fertilizer usage.
The addition of meso- and micro-elements can raise important physiological processes:
MAGNESIUM optimizes the photosynthetic cycle and the phosphate metabolism;
ZINC is an active element in many enzyme systems: it encourages the auxin growth, directly affects the nitrogen metabolism and the phosphorus absorption, beneficially fostering crop growth in the early vegetative stages.
  • Crop: BEET

    Beet: With placement underground, before winter.

  • Crop: CEREALS

    Wheat, Barley and Oat: At the pre-sowing stage, with placement underground.


    Sunflower: With placement underground, before winter.

  • Crop: CORN

    Corn, Sorghum: In the pre-sowing stage, with placement underground, at the end of winter.


Reference guidelines for individual crops are purely illustrative and are changeable, in relation to the needs, the fertility levels and the provisions of various regulations.

Organic fertilizers or soil conditioners: feeding farmed animals with herbage plants, or being taken across the pasture after the harvest is forbidden for at least 21 days after the application.

Do not dispose packaging in the environment. Avoid contact with eyes and skin.