Cool-Season, Warm-Season, or Transition Zone

Graphic of world nestled in blades of grass

There is no breed of grass able to thrive on both a Vermont ski slope and a Florida orange grove.  For this reason, grasses are divided into two main groups, cool-season, and warm-season, and then further divided into two subgroups,  transition zone and native.

Cool-Season Grasses

Cool-season grasses all thrive in northern areas, including Canada, as well as higher elevations farther south.  The main growing period for cool-season grass is in spring and fall when soil temperature is 50 to 65 degrees Fahrenheit, and the air temperature is 60 to 75 degrees Fahrenheit.  Come high summer, cool-season grasses go dormant unless regularly irrigated.  Kentucky bluegrass, bentgrass, ryegrass, and the fescues are all cool-season grasses.

Warm-Season Grasses

Warm-season grasses grow best in southern regions.  The main growing period for warm-season grass is in the summer when soil temperature is between 70 and 90 degrees Fahrenheit, and the air temperature is 80 to 95 degrees Fahrenheit.  Warm-season grasses become dormant with the onset of cooler weather.  The degree of tolerance of warm-season grasses varies by cultivar, but many turn straw-colored or light brown after the first frost.  The bermuda, St. Augustine, and zoysia grasses are just a few species found in this group.

Transition Zone Grasses

Transition zone grasses can adapt to the climate in the band across the country where north meets south.  This zone extends from southern California, east through Oklahoma and Kansas, to the eastern coastal states of Virginia, the Carolinas, and Georgia.  Tall fescues and zoysia grass are the two grasses most frequently used in the transition zone.

Native Grasses

Native, or prairie, grasses have adapted to the arid conditions of the Great Plains.  Drought resistance and a preference for neglect are their most desirable qualities.  Buffalograss, wheatgrass, and Blue grama are all native grasses that cope well under these conditions.

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