Kentucky climate

Kentucky Plant Hardiness Zones

Kentucky’s towns run from zone 6b to zone 7b: the average coldest winter night is 6.4°F at Murray and -4°F at Bedford.

Hardiness zones in Kentucky

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 Kentucky, from zone 6b to zone 7b, with the state’s border drawn.
  • 6b
  • 7a
  • 7b

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.

7b Zone 7b, 5 to 10°F 13 towns

7a Zone 7a, 0 to 5°F 265 towns

6b Zone 6b, -5 to 0°F 97 towns

Counties

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

CountyZone at the centerAverage coldest night
Adair County7a1.4°F
Allen County7a4.2°F
Anderson County6b-1.1°F
Ballard County7a3.9°F
Barren County7a3.8°F
Bath County6b-0.5°F
Bell County7a3.1°F
Boone County6b-2.4°F
Bourbon County6b-0.5°F
Boyd County7a0.5°F
Boyle County7a1°F
Bracken County6b-1°F
Breathitt County7a1.6°F
Breckinridge County7a0.6°F
Bullitt County7a1.7°F
Butler County7a1.2°F
Caldwell County7a3.4°F
Calloway County7b6°F
Campbell County6b-1.1°F
Carlisle County7a4.5°F
Carroll County6b-0.4°F
Carter County6b-2.8°F
Casey County7a0.7°F
Christian County7a4.2°F
Clark County7a0.2°F
Clay County7a2.8°F
Clinton County7a3.4°F
Crittenden County7a3.4°F
Cumberland County7a1.1°F
Daviess County7a2.4°F
Edmonson County7a1.4°F
Elliott County6b-2.6°F
Estill County6b-1.5°F
Fayette County7a0.7°F
Fleming County6b-0.7°F
Floyd County7a1.4°F
Franklin County6b-0.6°F
Fulton County7b5.5°F
Gallatin County6b-1.8°F
Garrard County7a0.9°F
Grant County6b-1.2°F
Graves County7b5°F
Grayson County7a1°F
Green County7a2.2°F
Greenup County6b-0.9°F
Hancock County7a2.3°F
Hardin County7a0.9°F
Harlan County7a3.5°F
Harrison County6b-1.4°F
Hart County7a2°F
Henderson County7a1.3°F
Henry County6b-2.2°F
Hickman County7b5.1°F
Hopkins County7a3.1°F
Jackson County6b-0.5°F
Jefferson County7a4.1°F
Jessamine County7a0.8°F
Johnson County7a0.3°F
Kenton County6b-1.1°F
Knott County7a1.6°F
Knox County7a3.1°F
Larue County7a1°F
Laurel County7a2.9°F
Lawrence County6b-2.1°F
Lee County7a0.5°F
Leslie County7a1.9°F
Letcher County7a1.7°F
Lewis County7a0.5°F
Lincoln County7a1°F
Livingston County7a4.3°F
Logan County7a3.9°F
Lyon County7b5°F
Madison County7a0.5°F
Magoffin County7a0.1°F
Marion County7a0.7°F
Marshall County7a4.4°F
Martin County7a2.9°F
Mason County6b-1.4°F
McCracken County7a3.5°F
McCreary County7a1.6°F
McLean County7a1.7°F
Meade County7a0°F
Menifee County7a1.6°F
Mercer County7a0.2°F
Metcalfe County7a2°F
Monroe County7a4.5°F
Montgomery County6b-0.7°F
Morgan County6b-2.1°F
Muhlenberg County7a2.2°F
Nelson County7a0.8°F
Nicholas County6b-0.7°F
Ohio County7a1.3°F
Oldham County6b-1.1°F
Owen County6b-1.2°F
Owsley County6b-1.1°F
Pendleton County6b-1.2°F
Perry County7a2.2°F
Pike County7a1.1°F
Powell County6b-0.5°F
Pulaski County7a2.7°F
Robertson County6b-1.1°F
Rockcastle County7a0.8°F
Rowan County6b-0.3°F
Russell County7a2.2°F
Scott County7a0.1°F
Shelby County6b-3.2°F
Simpson County7a4.2°F
Spencer County6b-0.3°F
Taylor County7a1.6°F
Todd County7a3.3°F
Trigg County7a3.5°F
Trimble County6b-3°F
Union County7a2.6°F
Warren County7a3.4°F
Washington County7a0.7°F
Wayne County7a1.8°F
Webster County7a2.9°F
Whitley County7a1.7°F
Wolfe County7a0.9°F
Woodford County7a0.1°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
6b-5 to 0°F-20.6 to -17.8°C
7a0 to 5°F-17.8 to -15.0°C
7b5 to 10°F-15.0 to -12.2°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.