Comparing Cool Season and Warm Season Grasses

Turf species are broken down into two categories: cool season and warm season grasses. As the name implies, cool season grasses prefer the cooler weather of northern climates. They grow the fastest during the fall and spring, preferring temperatures between 50 and 80 degrees. Cool season grasses stay green until temperatures drop below 32 degrees F for extended periods and can survive subfreezing temperatures. Conversely, warm season grasses prefer the heat of southern climates. They grow the fastest during the summer, preferring temperatures between 80 and 95 degrees. They lose their green color if winter temperatures drop below 50 degrees F for extended periods of time; some species cannot survive extended periods of subfreezing temperatures.

Growing The Right Grass

Having the right grass type for your climate is one of the most important factors for a thriving lawn. It’s helpful to know each grass type’s strengths and weaknesses too, especially when:

Transition Zone Grasses

Some species can survive in both their preferred climate and in the transition zone: the area which is both hot in the summer and cold in the winter. In the United States, the transition zone encompasses the eastern central and the mid-central regions of the country. Bermuda and Tall fescue type grasses are the most commonly grown grass types in the transition zone. Bermuda being a warm season grass is more widely grown in the southern edge of the transition zone. Tall fescue, an adaptable cold season grass, is generally the choice for central and northern transition zone areas. There are several subclimates in the transition zone, so what works best in Norfolk, VA won’t be the same as Flagstaff, AZ.

Grass Species Superpowers

In addition to preferring warmer or cooler temperatures, different species of grass have different tolerances for a number of traits (drought tolerance, shade tolerance, etc.). Below are relative rankings for the following traits in common lawn turf grasses: heat, cold, drought, and shade. Remember, climate type is always the first and most important thing to consider.

Cool Season Grass Tolerances

Common Cool Season Grass types include: Tall Fescue, Fine Fescue, Kentucky Bluegrass, Perennial Ryegrass, Annual Ryegrass.

Warm Season Grass Tolerances

Common Warm Season Grass types include: Zoysia, Bermudagrass, Kikuyugrass, Bahiagrass, St. Augustine, and Centipede Grass.

There's Always An Exception

Keep in mind, there are always exceptions. Zoysia, a warm season grass can do okay in Chicago or New York, but will have a longer dormancy period. Tall Fescue, a cool season grass can survive in west Texas and Southern Arizona, but will need much more water.

Unsure what grass will do best in your climate? Ask a lawn expert.