Grupa Kapitałowa Grupa Azoty
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Nitrogen fertilizers with sulfur


N(MgS) 21-(4-35)
Fertilizer from mixing of fertilizer types with the EC mark: type A.1.4 and A.1.9

Trade name: POLIFOSKA® 21
Name: Fertilizer N(Mg,S)
PKWiU: 20 15 390
CN: 31 029 000 90

Grupa Azoty Police

Fertilizer of uniform, light grey granules (grain class 2-5 mm, at least 92%), covered with anti-caking agents, without permanent caking characteristics. Hygroscopic. Bulk density: 0.90-1.00 kg/dm3.
POLIFOSKA® 21 includes 21% of nitrogen (N), including 8% in amides and 13% in nitrates. The fertilizer includes 4% of total magnesium (MgO) in the form of carbonate and sulphate soluble in water and 35% of sulphur trioxide (SO3), that is, 14% of sulphur soluble in water, in sulphate form. It results from the mixing of ammonium sulphate, urea and fine-ground magnesite.
The amide form of nitrogen is converted in soil into the ammonia form available for plants, and then into nitrate form. These processes are quite slow, making the nitrogen available to plants uniformly. Losses of nitrogen from soil are low, because it is not washed out of soil.

Intended use and applicationSee more
It is recommended that this fertilizer be used in spring, for top dressing on winter plants, especially on winter rape and winter crops. It is also recommended for use in spring under all other cultivated plants: spring crops, corn, economic and root plants and in cultivation of vegetables and fruit cultures. It is indispensable in fertilization of crucifer plants (rape, oil-yielding rape, mustard, cabbage, cauliflower, cabbage turnip), leguminous plants, potato, onion, leek, garlic and horseradish. It is very effective on organic soil, especially on grassland. When using POLIFOSKA® 21 prior to sowing, it is best mixed shallow with soil (several cm). Permanent crops may be fertilized in spring. 
On account of its hygroscopicity, POLIFOSKA® 21 may be mixed immediately before spreading with POLIDAP®, POLIFOSKA®, POLIMAG® S and potash salt. 
Advantages:An advantage of this fertilizer is the possibility of applying nitrogen and sulphur in spring. The high sulphate sulphur content, perfectly soluble in water, increases the immunity of plants and provides them with sulphur early in spring growth. The addition of easily soluble magnesium in the initial phases of shallow-rooted plants improves early spring intake of nutrients. This chemical composition in a fertilizer results in good rooting and proper development of plants from early spring, increases their strength and contributes to an improvement in quality and a faithful and high yield.
Packaging and transportSee more
POLIFOSKA® 21 is packaged in:
  • 50 kg ± 1% polyethylene bags with overprint;
  • Flexible containers at 500 kg ± 1% or more, the so-called big-bags.
The fertilizer must be transported while protected against water, rainfall, direct sunlight and damage to the packaging.
POLIFOSKA® 21 is not classified, i.e. it is not considered a hazardous material according to the UN Orange Book and international transport codes, for example RID (railway transport), ADR (road transport) and IMDG (sea transport).
With regard to transportation using the road vehicles of the recipient or of a carrier acting on the direct instructions of the recipient, it is the recipient or the carrier who is responsible for any deterioration in the quality of the fertilizer.
StorageSee more
Polyethylene bags with overprint of a net content of 50 kg should be stored in 10 layers at the most. Flexible containers of less than 500 kg in weight may be stored in piles of up to two layers, or in piles of one layer if weight exceeds 500 kg. In the case of pallet storage, loading units of up to 0.9 m in height are stored in piles of four layers, and loading units of 0.9 m to 1.8 m in height in piles of not more than 3.6 m.
The fertilizer should be stored in clean and dry warehouse buildings and protected against atmospheric conditions (solar radiation, rainwater). 
In the course of transportation, handling and storage, the regulations in force should be observed.
PrecautionsSee more

In the event of irritation of skin and eyes, wash with plenty of water. Dust masks and safety goggles are recommended. If swallowed accidentally, seek medical advice. Nontoxic, odourless, non-flammable fertilizer.

Support and consultingSee more

Aiming to provide the highest standards of customer service, the Grupa Azoty offers professional consulting, information support for farmers and food producers.

Support includesSee more


  • Client support with technical knowledge, i.e. consulting in fertilizer use
  • Resolution of problems reported by the client (dosage, chemical composition of fertilizers, mechanisms of effect on cultivated plants and elements of the natural environment)
  • Provision of information on distribution centres in the country
  • Information on the current fertilizer product range of the Grupa Azoty


Paulina Czerniak - product manager
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