Plant nutrients, divided into macronutrients and micronutrients are indistinguishable, whether they are from organic or chemical sources. All must be water soluble in order to enter plant root systems.

Macronutrients are nitrogen (N), phosphate (P), potash (K), sulphur (S), calcium (Ca) and magnesium (Mg). The oxygen (O), hydrogen (H) and carbon (C) come from air and water and make up 95 to 99% of a plant’s weight.

In almost all soils above pH 6 calcium and magnesium are generally present in non-limiting quantities.

In fertile soils typical of the prairies, following repeated crop removal, nitrogen, sulphur and phosphate are the first to become growth limiting. In acidic soils below pH 5, typical of higher rainfall areas potassium, calcium and magnesium may also become growth limiting. When soil pH’s are on the acid side (below pH 5) we add Ca in the form of lime, calcium hydroxide, limestone (calcium carbonate) or dolomitic limestone (a combination of calcium and magnesium carbonate) to bring up the pH to 6 or higher.

Micronutrients are needed in only very small quantities but they are every bit as essential as macronutrients to normal plant growth. Plant essential micronutrients are boron (B), chloride (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn) and if deficient they are applied to soil in pounds per acre.