Answer by
BrendaG (6111)
Potassium, phosphorus, and nitrogen, called fertilizer macronutrients, are the basics. Next are the secondary macronutrients that include sulfur, calcium, and magnesium. Also present are micronutrients called trace minerals. Nitrogen makes it grow, phosphorus encourages rooting thru production, and potassium helps prevent plant disease. These three represent the numbers on bag.