Fertilizers and Fertilizer Management

Fertilizers, in a broad sense, include all materials that are added to soils to supply certain elements essential to the growth of plants.   However, fertilizer usually refers to chemical fertilizers and unlike in manures, the nutrient elements in fertilizers are present in higher concentrations and in forms which can be readily assimilated by plants.  Sulphur, nitrogen, phosphorus and potassium are the macronutrients applied in commercial fertilizers.