When Does Turf Grass Grow?

Warm Season Grass

• Warm season grass types such as bahia, St. Augustine, Bermuda, centipede and zoysia start growing when soil temperatures are between 65 to 75 degrees Fahrenheit, according to Virginia Cooperative Extension. The growth rate of Bermuda grass declines when temperatures dip below 50 degrees Fahrenheit, according to Texas A&M University. However, Bermuda grass's roots will continue to grow for a few weeks after the blades have turned brown and have gone dormant for the growing season.

Cool Season Grass

• Cool season grass varieties such as fescues, ryegrasses and bluegrasses thrive when air temperatures are below 80 degrees Fahrenheit, according to Purdue University. In fact, Kentucky bluegrass's growth declines when temperatures exceed 70 degrees Fahrenheit and roots thrive when soil temperatures are around 60 degrees Fahrenheit. Grass roots will continue to grow in cool air temperatures as long as the soil temperatures do not dip below 45 degrees Fahrenheit or the ground freezes. Some cool season yards may look like they have gone dormant, but their roots are still growing.

Time of Year

• Generally, warm season grass begins to grow in early spring in the southern regions in the United States or in early summer in the transition zone -- a band of states between the southern and northern parts of the United States. Kentucky, West Virginia and Tennessee are a few of the states in this zone. Cool season grass begins to grow in the fall and spring in the northern parts of the United States.

Fertilizing

• Fertilizing in the fall helps grass maintain root growth during cool weather and minimizes your weed population. Both warm season and cool season grass types can benefit from a fall fertilizer application. Cool season grass can use the nutrients to spread throughout the yard, whereas warm season grass uses the stored carbohydrates it generates from the fertilizer to green up in the spring. Typically, you can spread one pound of fertilizer per 1,000 square feet in the fall for almost any grass type.