Tennessee climate

Tennessee Plant Hardiness Zones

Tennessee’s towns run from zone 7a to zone 8a: the average coldest winter night is 13.2°F at Memphis and 0°F at Mountain City.

Hardiness zones in Tennessee

In USDA’s colors, neighboring states washed out. Zones follow elevation, coasts and cities down to half a mile. Drawn by WeatherOverTime from the USDA-ARS and Oregon State University PRISM Climate Group 2023 GIS data; this is not the official USDA Plant Hardiness Zone Map.

Map of the 2023 plant hardiness zones across Tennessee, from zone 6a to zone 8a, with the state’s border drawn.
  • 6a
  • 6b
  • 7a
  • 7b
  • 8a

Open the live map with plant hardiness zones

Towns by zone

Each town’s 1991-2020 average annual extreme minimum at its center, read from the map’s 800 m grid. Warmest zone first.

8a Zone 8a, 10 to 15°F 46 towns

7b Zone 7b, 5 to 10°F 265 towns

7a Zone 7a, 0 to 5°F 60 towns

Counties

At the county’s center; a county with hills or a coast spans several zones.

CountyZone at the centerAverage coldest night
Anderson County7b8.2°F
Bedford County7b6.8°F
Benton County7b7.4°F
Bledsoe County7b7.6°F
Blount County7b8.6°F
Bradley County7b8.4°F
Campbell County7b7.1°F
Cannon County7b6.2°F
Carroll County7b7.8°F
Carter County7a3.1°F
Cheatham County7b5°F
Chester County7b8.6°F
Claiborne County7a3.6°F
Clay County7a3.7°F
Cocke County7b7.6°F
Coffee County7b6.8°F
Crockett County7b9.4°F
Cumberland County7a1.9°F
Davidson County7b8°F
Decatur County7b7.8°F
DeKalb County7b5.4°F
Dickson County7b6.4°F
Dyer County7b9.3°F
Fayette County8a10°F
Fentress County7a1.9°F
Franklin County7b8.2°F
Gibson County7b7.8°F
Giles County7b8.3°F
Grainger County7b6.5°F
Greene County7a3.7°F
Grundy County7a3.1°F
Hamblen County7b7.3°F
Hamilton County8a10.9°F
Hancock County7a4.6°F
Hardeman County7b9.9°F
Hardin County7b8.6°F
Hawkins County7b6°F
Haywood County8a10.2°F
Henderson County7b8.3°F
Henry County7b5.8°F
Hickman County7b6°F
Houston County7b5.8°F
Humphreys County7b6.2°F
Jackson County7a4.9°F
Jefferson County7b7.2°F
Johnson County6b-0.3°F
Knox County7b8.4°F
Lake County7b7.8°F
Lauderdale County8a10.1°F
Lawrence County7b7.5°F
Lewis County7b6.8°F
Lincoln County7b8.6°F
Loudon County7b8.2°F
Macon County7b6.2°F
Madison County7b9.6°F
Marion County7b7.1°F
Marshall County7b6.2°F
Maury County7b6.7°F
McMinn County7b7.9°F
McNairy County7b8.5°F
Meigs County7b6.8°F
Monroe County7b7.9°F
Montgomery County7b5.9°F
Moore County7b7.5°F
Morgan County7b6.4°F
Obion County7b5.6°F
Overton County7a4.5°F
Perry County7b6.1°F
Pickett County7a2.2°F
Polk County7b8.9°F
Putnam County7a4.9°F
Rhea County7b7°F
Roane County7b8.9°F
Robertson County7a4.3°F
Rutherford County7b6.4°F
Scott County7a1.9°F
Sequatchie County7b9.8°F
Sevier County7b7.4°F
Shelby County8a12.6°F
Smith County7b7°F
Stewart County7b6.5°F
Sullivan County7b5°F
Sumner County7b5.4°F
Tipton County8a11.3°F
Trousdale County7b6.1°F
Unicoi County7a3.6°F
Union County7b5.3°F
Van Buren County7a2.8°F
Warren County7b7.1°F
Washington County7a4.9°F
Wayne County7b6.3°F
Weakley County7b6.2°F
White County7b6.7°F
Williamson County7b7°F
Wilson County7b6.7°F

The zones

A plant hardiness zone is set by the average of each winter’s single coldest temperature, 1991 to 2020: zones are 10°F apart and each half zone, a and b, 5°F. It says how cold a winter night usually gets, not the coldest it has ever been, and nothing about summer heat, rain or soil. Plant labels give the coldest zone a perennial survives in.

ZoneAverage coldest nightIn Celsius
7a0 to 5°F-17.8 to -15.0°C
7b5 to 10°F-15.0 to -12.2°C
8a10 to 15°F-12.2 to -9.4°C

Sources

Hardiness zones: USDA Plant Hardiness Zone Map, 2023, Agricultural Research Service, U.S. Department of Agriculture, from the GIS data of the PRISM Climate Group, Oregon State University, which may be freely reproduced and redistributed. Drawn by WeatherOverTime from the USDA-ARS and Oregon State University PRISM Climate Group 2023 GIS data; this is not the official USDA Plant Hardiness Zone Map.