New Jersey climate

New Jersey Plant Hardiness Zones

New Jersey’s towns run from zone 6b to zone 8a: the average coldest winter night is 11.5°F at Brigantine and -4.3°F at Sussex.

Hardiness zones in New Jersey

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 New Jersey, from zone 6b to zone 8a, with the state’s border drawn.
  • 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 12 towns

7b Zone 7b, 5 to 10°F 255 towns

7a Zone 7a, 0 to 5°F 276 towns

6b Zone 6b, -5 to 0°F 46 towns

Counties

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

CountyZone at the centerAverage coldest night
Atlantic County7a4.3°F
Bergen County7a4.2°F
Burlington County7a3.9°F
Camden County7a4.8°F
Cape May County7b8.4°F
Cumberland County7b6.3°F
Essex County7a2.4°F
Gloucester County7b7°F
Hudson County7b7.6°F
Hunterdon County7a0.3°F
Mercer County7a4.8°F
Middlesex County7a4°F
Monmouth County7a4.7°F
Morris County6b-2.2°F
Ocean County7a3.4°F
Passaic County7a2.1°F
Salem County7b8.5°F
Somerset County7a2.8°F
Sussex County6b-4.2°F
Union County7a4.4°F
Warren County6b-0.3°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
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.