Lawn Fertilization

January 10, 2014

Today, temperatures finally began to climb out of the negatives. With the onset of warmer weather, (using this term gently) I felt it was a good time to start looking towards spring. Over the last few months there have been several inquiries regarding lawn fertilization. In response, I have revised the Iowa State University home lawn fertilization publication. Although you will not be pulling out the fertilizer bag for another 4-5 months, I thought I would inspire you with some information that will get you ready for warmer weather. The publication outlines the importance of fertilization, rates and timing of application, label requirements in Iowa, and fertilizer products in the market.


The following is a small excerpt from the introduction.

Lawns are an important component of many home landscapes. Good cultural practices are necessary to achieve a healthy, attractive lawn. One important cultural practice is fertilization. The benefits of a well-maintained lawn fertilization program are good turf color, quality and density. There are 14 elements which are often referred to as mineral nutrient elements and are generally obtaining in the soil via root extraction. The quantity of most of these nutrients contained in the soil is high compared with the requirements of turfgrass plants. However the demands for nitrogen, phosphorus, and potassium oftenexceed the supply in the soil. Thus, it becomes necessary to add these elements through fertilization.

Turfgrasses require nitrogen (N) in the largest amount of any of the essential nutrients. For this reason, nitrogen is usually applied in the largest amounts. Nitrogen nutrition is important to turfgrasses because it canaffect shoot growth and density, root growth, and susceptibility to damage from disease, heat, cold, and drought.

Turfgrasses require potassium (K) in relatively large amounts, second only to nitrogen. Potassium influences turfgrass rooting, disease susceptibility and drought, heat, and cold hardiness. The terms soluble potash, soluble potassium and K20 may be used to refer to potassium fertilization. 

Phosphorus (P) is required by turfgrass plants in smaller amounts than nitrogen and potassium. Phosphorus is important in the establishment, rooting, maturation,and reproduction of turfgrasses. The terms available phosphate, available phosphorus, available phosphoric acid, and P2O5may be used to refer to phosphorus fertilization. 

The entire extension publication is attached in pdf form.  To download the publication, click on the following link Fertilizer Publication.