What is the difference between cool-season and warm-season grass?

NC State Extension says cool-season grasses grow best in spring and fall and less actively in summer, and stay green through most of the winter. Warm-season grasses are slow to green up in spring, grow best in summer, and go dormant after the first heavy frost.

Which grasses are cool-season and which are warm-season?

NC State Extension lists tall fescue, Kentucky bluegrass, fine fescue and perennial ryegrass as common cool-season grasses. Bermudagrass, zoysiagrass, centipedegrass, St. Augustinegrass, bahiagrass and buffalograss are warm-season.

What is the transition zone?

The band where both kinds of grass can grow and neither is fully at home. Clemson describes Bermudagrass as used into the transition zones where both cool-season and warm-season grasses are adapted. In South Carolina, Clemson says heat stress rules out cool-season grasses as permanent lawns except tall fescue in the upper Piedmont and mountains, above about 800 feet.

Can I grow Kentucky bluegrass in the South?

As a permanent lawn, rarely. Clemson says northern grasses such as fine fescue, Kentucky bluegrass and ryegrass grow in South Carolina only in fall, winter and early spring, as overseeding, and do not survive year-round. NC State rates Kentucky bluegrass for zones 3a to 7b.

Why does the kind of grass matter for lawn care?

Because the two kinds need opposite timing. Clemson says fescue lawns are fertilized in fall, while warm-season grasses such as centipede, St. Augustine, Bermuda and zoysia can be injured by nitrogen applied in fall. NC State seeds cool-season grasses in early fall and plants warm-season grasses in late spring and early summer.

Guides

Cool-Season vs Warm-Season Grass: Which Lawn Grass by Zone

Every lawn job, from feeding to the last mow, starts with one question: is your grass a cool-season grass that grows in spring and fall, or a warm-season grass that grows in summer and goes brown in winter? This page shows which grasses NC State rates for each USDA zone, where the two kinds meet, and what the answer decides.

Published October 27, 2026 · Cite this page

Two kinds of lawn grass

Cool-season grasses grow best in spring and fall and less actively in summer, and remain green through most of the winter, NC State Extension says. It names tall fescue, Kentucky bluegrass, fine fescue and perennial ryegrass as the common ones. Iowa State University Extension and Outreach says Kentucky bluegrass is the best choice for sun there, and that the fine-leaf fescues are the best grasses for shade.

Warm-season grasses are slow to green up in spring, grow best in summer, and go dormant after the first heavy frost, turning brown until spring (NC State). Bermudagrass, zoysiagrass, centipedegrass, St. Augustinegrass and bahiagrass are the Southern ones; buffalograss is native to the central United States. NC State says some warm-season grasses have to be planted as sod or plugs because seed is not available or does not give an even stand.

Which grasses are rated for your zone

Each grass’s zone range is NC State Extension’s plant toolbox rating for it, read on 27 October 2026. A rating is a judgement, not a measurement, and NC State writes for North Carolina. The freeze dates are each zone’s median NOAA station.

Zone	Cool-season grasses rated	Warm-season grasses rated	First fall freeze, median	Last spring freeze, median	Stations · ZIP codes
Zone 3	Kentucky bluegrass, Fine fescue (creeping red fescue), Perennial ryegrass	None rated	September 22	May 19	98 · 253
Zone 4	Kentucky bluegrass, Fine fescue (creeping red fescue), Perennial ryegrass	Buffalograss	September 28	May 13	698 · 2,098
Zone 5	Kentucky bluegrass, Fine fescue (creeping red fescue), Perennial ryegrass	Buffalograss, Zoysiagrass	October 5	May 6	1,307 · 5,306
Zone 6	Kentucky bluegrass, Fine fescue (creeping red fescue), Perennial ryegrass	Buffalograss, Zoysiagrass, Bermudagrass	October 17	April 28	1,728 · 10,458
Zone 7	Kentucky bluegrass, Perennial ryegrass	Buffalograss, Zoysiagrass, Bermudagrass, Centipedegrass, St. Augustinegrass	October 26	April 14	1,428 · 8,732
Zone 8	Perennial ryegrass	Buffalograss, Zoysiagrass, Bermudagrass, Centipedegrass, St. Augustinegrass, Bahiagrass	November 9	March 26	1,253 · 6,809
Zone 9	None rated	Zoysiagrass, Bermudagrass, Centipedegrass, St. Augustinegrass, Bahiagrass	December 1	February 25	736 · 4,284
Zone 10	None rated	Zoysiagrass, Bermudagrass, Centipedegrass, St. Augustinegrass, Bahiagrass	January 1	January 18	234 · 1,986

⚠️ Tall fescue is left out of the zone rows because NC State’s toolbox gives it no zone range; it is the most widely grown cool-season lawn grass in North Carolina, and Clemson recommends it only for the Piedmont and mountains of South Carolina. A zone is the coldest winter night and says nothing about summer heat, which is what ends a cool-season lawn in the South — why your hardiness zone is not a planting date. For your own zone and station, enter your ZIP code below.

The ten grasses

Grass	Kind	NC State zones	What the sources say
Kentucky bluegrass Poa pratensis	Cool-season	3a–7b	Spreads by rhizomes to form a mat; in the Piedmont it is often mixed with tall fescue and needs afternoon shade in hot Southern summers (NC State).
Fine fescue (creeping red fescue) Festuca rubra	Cool-season	3a–6b	Does well in part shade and cool climates (NC State). Iowa State calls the fine-leaf fescues the best grasses for shady sites.
Perennial ryegrass Lolium perenne	Cool-season	3a–8b	Quick to germinate and usually mixed with Kentucky bluegrass; in the South it is sown into Bermudagrass for winter color and seldom survives the onset of warm weather (NC State).
Tall fescue Lolium arundinaceum (Schedonorus arundinaceus)	Cool-season	No zone rating	The most widely grown cool-season lawn grass in North Carolina, tolerant to heat and drought (NC State). Clemson recommends it only for the Piedmont and mountain areas of South Carolina.
Buffalograss Bouteloua dactyloides	Warm-season	4a–8b	A native of the central US; turns straw-colored when dormant from mid-fall to mid-spring and greens up quickly in spring (NC State).
Zoysiagrass Zoysia japonica, Z. matrella and others	Warm-season	5a–11a	NC State calls zoysiagrasses high-maintenance grasses; seed is sold for Japanese lawngrass (Z. japonica), but sod or plugs are usually used to start a lawn.
Bermudagrass Cynodon	Warm-season	6a–10b	Takes heavy traffic, but spreads vigorously; NC State lists it as invasive in North Carolina and suggests zoysia, St. Augustine or centipede for a home lawn.
Centipedegrass Eremochloa ophiuroides	Warm-season	7a–10b	A low-maintenance Southern lawn grass for acid soil; it does not take traffic, high pH, drought or heavy shade (NC State).
St. Augustinegrass Stenotaphrum secundatum	Warm-season	7a–12b	Heat tolerant and mildly drought tolerant; NC State says it is sold as sod or plugs and is rarely grown from seed.
Bahiagrass Paspalum notatum	Warm-season	8a–10b	Easy to establish by seed; NC State does not recommend it as a lawn grass because of its tall seed heads and open canopy.

The transition zone

Where the cool-season and warm-season ranges overlap, both kinds of grass grow and neither has an easy time. Clemson Cooperative Extension says Bermudagrass is used throughout the southern United States and into the transition zones where both kinds are adapted. In the zone table above, that overlap is zones 6 to 8: NC State rates cool-season grasses up to zone 8 (perennial ryegrass) and Bermudagrass from zone 6a.

Summer heat, not winter cold, decides which side of it you are on. Clemson says heat stress rules out most cool-season grasses as permanent Southern lawns, with the exception of tall fescue in the upper Piedmont and mountains above about 800 feet, and that the northern grasses survive in South Carolina only as winter overseeding. UGA Extension calls tall fescue best adapted to Georgia’s Piedmont. In the Piedmont, Clemson adds, centipedegrass does best in open sun on south- or southwest-facing slopes and can suffer winter kill on north-facing slopes or in shade.

So in the transition zone, ask your county extension office which grasses do well on your street, and look at what grows well in your neighbors’ lawns: the zone table gives the range, not the answer for one yard.

What the choice decides

When to fertilize. Clemson feeds fescue in fall; it says warm-season grasses can be injured by nitrogen applied in fall, and should get their last at least two months before the first average frost. Fertilizer timing by zone.
When to seed. NC State seeds cool-season grasses in early fall and plants warm-season grasses in late spring and early summer; a warm-season lawn is only overseeded, with ryegrass, for winter color. Overseeding dates by zone.
When to aerate. NC State cores cool-season grasses in fall or early spring and warm-season grasses in late spring or early summer. Aeration timing by zone.
When to stop mowing, and how a lawn spends the winter. A cool-season lawn stays green into the cold; a warm-season lawn turns brown at the first heavy frost and is dormant, not dead. The last mow by zone and winter lawn care.

Supplies

Supplies the sources mention

Each link opens an Amazon search for a plain kind of product, not one we picked. We have not tested these, and we do not rank them.

As an Amazon Associate I earn from qualifying purchases. It costs you nothing extra and changes nothing on this page: the dates are NOAA’s and the advice is the extension services’. Affiliate disclosure

Soil test kitPenn State Extension says only a soil test tells you how much phosphate and potash a lawn needs, and Clemson bases every fertilizer and lime application on one. Your county extension office also tests soil.

Your ZIP code

Your ZIP, your answer

Enter your ZIP code to see your USDA zone, the lawn grasses NC State rates for the zone, and its freeze dates, read from the table on this page, and the freeze dates of the NOAA station nearest you.

This box needs JavaScript to answer on the page. Without it, the button opens the ZIP code zone finder; your zone’s row is in the table on this page.

Your answer appears here.

Full details for any ZIP code: ZIP code zone finder.

Common mistakes

Treating a zone rating as a heat rating. Clemson says heat, not cold, rules out cool-season lawns in most of South Carolina.
Feeding a warm-season lawn on a cool-season calendar. Clemson says fall nitrogen can injure warm-season grasses.
Overseeding centipede, zoysia or St. Augustine with ryegrass. Clemson recommends overseeding only on Bermudagrass.
Choosing bahiagrass for a fine lawn. NC State does not recommend it as a lawn grass, for its seed heads and open canopy.
Planting Bermudagrass beside beds. NC State lists it as invasive in North Carolina; it spreads into beds and borders.

Every lawn job by zone

Cool-Season vs Warm-Season Grass: Which Lawn Grass by Zone — this page
When to Fertilize Your Lawn by Zone
When to Overseed Your Lawn by Zone
When to Aerate Your Lawn by Zone
When to Stop Mowing: The Last Mow of the Year by Zone
Winter Lawn Care and Dormant Lawns, by Zone
Fall Lawn Care by Region: Fertilize, Aerate, Overseed
Your USDA hardiness zone by ZIP code

Where there is no source here

We found no Texas source on choosing a lawn grass that we could read: the Texas A&M AgriLife lawn pages we tried did not load. The zone ratings are NC State’s, written for North Carolina; Clemson writes for South Carolina, and Iowa State and Penn State for the Midwest and Northeast. Your state’s extension service publishes the grasses it recommends for your county.

Questions

What is the difference between cool-season and warm-season grass?: NC State Extension says cool-season grasses grow best in spring and fall and less actively in summer, and stay green through most of the winter. Warm-season grasses are slow to green up in spring, grow best in summer, and go dormant after the first heavy frost.
Which grasses are cool-season and which are warm-season?: NC State Extension lists tall fescue, Kentucky bluegrass, fine fescue and perennial ryegrass as common cool-season grasses. Bermudagrass, zoysiagrass, centipedegrass, St. Augustinegrass, bahiagrass and buffalograss are warm-season.
What is the transition zone?: The band where both kinds of grass can grow and neither is fully at home. Clemson describes Bermudagrass as used into the transition zones where both cool-season and warm-season grasses are adapted. In South Carolina, Clemson says heat stress rules out cool-season grasses as permanent lawns except tall fescue in the upper Piedmont and mountains, above about 800 feet.
Can I grow Kentucky bluegrass in the South?: As a permanent lawn, rarely. Clemson says northern grasses such as fine fescue, Kentucky bluegrass and ryegrass grow in South Carolina only in fall, winter and early spring, as overseeding, and do not survive year-round. NC State rates Kentucky bluegrass for zones 3a to 7b.
Why does the kind of grass matter for lawn care?: Because the two kinds need opposite timing. Clemson says fescue lawns are fertilized in fall, while warm-season grasses such as centipede, St. Augustine, Bermuda and zoysia can be injured by nitrogen applied in fall. NC State seeds cool-season grasses in early fall and plants warm-season grasses in late spring and early summer.

Sources

Dates on this page are computed when the site is built from NOAA's 1991–2020 Climate Normals (first fall freeze at 32 °F, for every station the ZIP codes in each zone cite). Zones are the USDA Plant Hardiness Zone Map, 2023. Every rule — how long before or after a freeze to plant, how deep, how much — is quoted from the extension publications below, each of which writes for its own area.

NC State Extension, Carolina Lawns: A Guide to Maintaining Quality Turf in the Landscape (AG-69) . Written for: North Carolina (USDA zones 6b–9a).
Clemson Cooperative Extension, Home & Garden Information Center, Selecting a Lawn Grass (HGIC 1214) , by Robert F. Polomski and Gary Forrester (Revised January 27, 2016). Written for: South Carolina (USDA zones 8a–9b).
Clemson Cooperative Extension, Home & Garden Information Center, Bermudagrass Maintenance Calendar (HGIC 1216) , by Trent C. Hale, Chuck Burgess and Gary Forrester (Revised November 2, 2018). Written for: South Carolina (USDA zones 8a–9b).
Clemson Cooperative Extension, Home & Garden Information Center, Winterizing Lawns (HGIC 1221) (Revised January 28, 2016). Written for: South Carolina (USDA zones 8a–9b).
UGA Extension, Clarke County, Shades of Green newsletter, September 2024 (seasonal calendar; excerpt of UGA Annual Publication 109, Fall Gardening) (September 2024). Written for: Clarke County (Athens), Georgia (USDA zones 8a–8b).
Iowa State University Extension and Outreach, Overseeding a Lawn . Written for: Iowa (USDA zones 4b–6a).
Penn State Extension, Lawn Management through the Seasons , by Peter Landschoot (Updated April 30, 2025). Written for: Pennsylvania (USDA zones 5b–8a).
NC State Extension Gardener Plant Toolbox, Poa pratensis (Kentucky bluegrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Festuca rubra (creeping red fescue) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Lolium perenne (perennial ryegrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Lolium arundinaceum (tall fescue) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Bouteloua dactyloides (buffalograss) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Zoysia (zoysiagrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Cynodon (bermudagrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Eremochloa ophiuroides (centipedegrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Stenotaphrum secundatum (St. Augustinegrass) . Written for: North Carolina (USDA zones 6b–9a).
NC State Extension Gardener Plant Toolbox, Paspalum notatum (bahiagrass) . Written for: North Carolina (USDA zones 6b–9a).

Nothing here replaces your own state's cooperative extension service, which knows your county. Where this site's numbers come from.

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