Plants are happy with nitrate as the only nitrogen source. Ammonium nitrate is preferred because it provides more nitrogen per weight, i.e. at similar transpor

Plants are happy with nitrate as the only nitrogen source. Ammonium nitrate is preferred because it provides more nitrogen per weight, i.e. at similar transportation costs with the alternatives, and also because introducing a too great amount of metal cations together with the nitrate, e.g. potassium or calcium, can be detrimental for the soil and can make it too alkaline after the nitrate is consumed.