Nutrient content

POLY4 is a unique four-in-one multi-nutrient fertilizer

POLY4’s four macro nutrients, as stated on its label, are 14% K2O, 17% CaO, 6% MgO and 19% S*[1].

Label declared analysis of a fertilizer is the minimum content of its nutrients or, in the case of undesirable elements, the maximum content of that element. It is most commonly expressed as a percentage by weight.

POLY4's chemical formula
K2SO4 MgSO4 2CaSO4 2H2O.
Figure 1: Nutrient content of major potash fertilizers

[1] SGS France Analysis (Nov 2014), 95% confidence interval for potassium, magnesium, calcium, sulphur and chloride.

*48% SO3