in K-Mag Fertilizer?
Sulfur (S) and sulfate sulfur (SO4) differences are explained just like Mg and MgO. The sulfur (S) content of K-Mag is 22%. When it is expressed in the oxide form, oxygen’s presence increases the sulfate sulfur content to between 63-66% as SO4. As with magnesium, the actual content is not changed by using different mathematical methods of expressing it.