PLANT NUTRIENTS 101
Turfgrasses require at least 16 nutrients for normal growth and development. Some nutrients are needed in large amounts, other nutrients only in minute quantities. Regardless of the amount required, a deficiency of any of these nutrients will limit the growth and development of your turf. Thus, a calcium deficiency can be just as detrimental to the plant as a lack of nitrogen, even though turfgrasses use more nitrogen than calcium.
Nine of the sixteen required nutrients are needed in much larger quantities than the other seven. These nine nutrients—carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur—are called macronutrients. Carbon, hydrogen, and oxygen make up about 90 to 95 percent of the plant’s dry weight. They are never deficient in turfgrasses because they are derived from carbon dioxide (CO 2 ) and water (H 2 O).
Nitrogen, phosphorus, and potassium are referred to as primary nutrients and must be supplied periodically to turf through fertilizer applications. Calcium, magnesium, and sulfur, the secondary nutrients, are needed only occasionally in the form of fertilizer or lime.
The seven micronutrients (sometimes called trace elements) required by turfgrasses include iron, manganese, zinc, copper, molybdenum, boron, and chlorine. Micronutrients are needed by turfgrasses only in minute amounts and rarely need to be supplied to turfgrasses growing in mineral soils. However, when turfgrasses are grown in high-sand-content soils (golf course putting greens and some tees) or high-pH soils, micronutrient applications can be beneficial.
Source: Penn State College of Agricultural Sciences