Lawn Fertilizer: Recommended Composition

Elements

• The primary elements for a healthy lawn include nitrogen (N), phosphorus (P) and potassium (K) obtained through water and air. Other elements that contribute to a healthy lawn are hydrogen, carbon and oxygen also derived mostly from air and water. Elements found in soils involve mostly metals like manganese, copper, nickel, iron and zinc in addition to chlorine, boron, cobalt and molybdenum.

Fertilizer Contents

• Nitrogen is responsible for the green color and hearty growth of turfgrasses. Of all the elements, nitrogen is needed in the largest quantity; however, it is still possible to "burn" a lawn with too much nitrogen. So a common ratio between N, P and K is recommended. Percentages vary from commercial product to product, but the comparisons between them generally include twice as much nitrogen as potassium and twice as much potassium as phosphorus.

Commercial Products

• Most commercial fertilizers will include the highest percentages of N, with K as the next highest, followed by P. The rest of the fertilizer consists of trace quantities of minerals and other elements such as sulfates and plant foods. Prior to purchasing any commercial fertilizer product, read all label information and directions.

Measuring and Testing

• Before you apply any type of fertilizer whether it is commercial or organic, measure the size of your lawn since this has a bearing on how much fertilizer to add. Another factor to take into account is the existing pH levels of your soil. This determines the ratio of N, P and K needed to arrive at accepted levels. Depending on the elements already present, you may need to adjust the elements to accommodate these levels.