Ammonium nitrate is a white crystalline dry fertilizer with the chemical formula NH4NO3. Pure ammonium nitrate is water soluble and contains 35% nitrogen. Conditioning agents are added to ammonium nitrate so the typical analysis is 34% nitrogen (34-0-0).

How is ammonium nitrate made? Ammonium nitrate is made by reacting nitric acid with anhydrous ammonia under very carefully controlled conditions. The resulting material is further processed to form granular nitrogen fertilizer.

Normally contains 34.5% nitrogen by weight although some imported granular products have 33.5% or 34%N. Ammonium Nitrate contains half the nitrogen in the ammonium form and half in the fast-acting nitrate form.

Popular Brands in the UK include Nitram, Extran & Nitraprill. For regulatory reasons, Ammonium Nitrate can only be supplied in bags in the UK and not at all in Northern Ireland.