Michigan climate

Michigan Plant Hardiness Zones

Michigan’s towns run from zone 4a to zone 7a: the average coldest winter night is 1.1°F at South Haven and -27.5°F at Caspian.

Hardiness zones in Michigan

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 Michigan, from zone 4a to zone 7a, with the state’s border drawn.
  • 4a
  • 4b
  • 5a
  • 5b
  • 6a
  • 6b
  • 7a

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.

7a Zone 7a, 0 to 5°F 1 towns

6b Zone 6b, -5 to 0°F 120 towns

6a Zone 6a, -10 to -5°F 326 towns

5b Zone 5b, -15 to -10°F 50 towns

5a Zone 5a, -20 to -15°F 36 towns

4b Zone 4b, -25 to -20°F 10 towns

4a Zone 4a, -30 to -25°F 6 towns

Counties

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

CountyZone at the centerAverage coldest night
Alcona County5b-11.3°F
Alger County5b-12.8°F
Allegan County6a-7.2°F
Alpena County6a-8.9°F
Antrim County5b-14.1°F
Arenac County6a-9.6°F
Baraga County4b-20.6°F
Barry County6a-8.6°F
Bay County6a-7.5°F
Benzie County6b-3.7°F
Berrien County6a-5.8°F
Branch County6a-7.4°F
Calhoun County6a-8.5°F
Cass County6a-5.9°F
Charlevoix County6a-9.1°F
Cheboygan County5a-19.4°F
Chippewa County4b-21°F
Clare County5a-18.5°F
Clinton County6a-7.5°F
Crawford County5a-18.3°F
Delta County5b-14.3°F
Dickinson County4b-20.9°F
Eaton County6a-8.1°F
Emmet County5a-17.1°F
Genesee County6a-7.7°F
Gladwin County5b-11.3°F
Gogebic County4a-26.5°F
Grand Traverse County6a-7.4°F
Gratiot County6a-9.2°F
Hillsdale County6a-8°F
Houghton County5a-16.9°F
Huron County6a-6.9°F
Ingham County6a-8.3°F
Ionia County6a-7.6°F
Iosco County5b-10.2°F
Iron County4a-25.9°F
Isabella County6a-8.8°F
Jackson County6a-7.7°F
Kalamazoo County6a-6.8°F
Kalkaska County5a-17.3°F
Kent County6a-5.8°F
Keweenaw County5b-13.1°F
Lake County5a-16°F
Lapeer County6a-8.9°F
Leelanau County6b-1.6°F
Lenawee County6a-7.8°F
Livingston County6a-8.3°F
Luce County5a-18.6°F
Mackinac County5b-11.1°F
Macomb County6b-4.4°F
Manistee County6b-3°F
Marquette County5b-13.3°F
Mason County6b-2.9°F
Mecosta County5b-13.6°F
Menominee County5a-18.6°F
Midland County6a-7.4°F
Missaukee County5a-16.6°F
Monroe County6b-4.4°F
Montcalm County5b-10.6°F
Montmorency County5a-18.8°F
Muskegon County6b-3.8°F
Newaygo County5b-11.9°F
Oakland County6a-7°F
Oceana County6a-7.5°F
Ogemaw County5a-17.5°F
Ontonagon County5a-18.8°F
Osceola County5a-17.3°F
Oscoda County5a-18.9°F
Otsego County5a-16.7°F
Ottawa County6b-3.9°F
Presque Isle County6a-9.4°F
Roscommon County5a-16.9°F
Saginaw County6a-6.7°F
Saint Clair County6a-7.2°F
Saint Joseph County6a-7.9°F
Sanilac County6a-7.1°F
Schoolcraft County5b-14.7°F
Shiawassee County6a-7.7°F
Tuscola County6a-9.6°F
Van Buren County6b-1.5°F
Washtenaw County6a-8°F
Wayne County6b-3.5°F
Wexford County5a-16.4°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
4a-30 to -25°F-34.4 to -31.7°C
4b-25 to -20°F-31.7 to -28.9°C
5a-20 to -15°F-28.9 to -26.1°C
5b-15 to -10°F-26.1 to -23.3°C
6a-10 to -5°F-23.3 to -20.6°C
6b-5 to 0°F-20.6 to -17.8°C
7a0 to 5°F-17.8 to -15.0°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.