How often do you need to fertilize a lawn?

(Question)

How often does a lawn company need to fertilize the lawn? My current company does this five times now until the fall. Is this necessary?

(Answer)

The number of times you need to fertilize a lawn can depend on several factors:  type of fertilizer, type of lawn cover, local conditions, individual company practices and even client expectations.

With non-organic fertilizer it is common to apply it three to four times a year starting in the early spring, reducing it during the hot weather when grass growth slows or goes dormant, and starting again in the fall.  Basically, you want to fertilize when the grass is in a growth period. Some commercial fertilizers are ‘slow-release’ and provide nutrients gradually over time. With these products, you may be able to reduce the number of times you apply fertilizer in a season.

Organic fertilizers, such as compost, and other organic practices can greatly reduce the number of times you need to fertilize a lawn. Many people are changing their expectations on how a lawn should look and are using these organic, nature-friendly ways.

Most lawns will do well with one application of compost in the spring. Compost is partially decomposed organic matter that provides essential ingredients and improves the soil’s structure. Another useful practice is to leave short grass clippings on the lawn. They decompose and add organic matter. Grass clippings left on the lawn can reduce the need to fertilize by as much as 25%. Feed the soil and it feeds the grass.

Another organic approach is to incorporate Dutch white clover by seeding it into the existing lawn so that the clover eventually comprises 20-25% of the lawn.  The clover fixes nitrogen from the air into the soil making it accessible for the roots of the grass. Nitrogen is a valuable ingredient for grass growth. With this ‘grown-in’ source of nitrogen, additional chemical fertilizer is not necessary. Adding compost once a year in the spring is still a good practice to include with this type of lawn.