USDA Plant Hardiness Zones · 2023 map

What growing zone is North Dakota?

North Dakota’s ZIP codes span USDA plant hardiness zones 3b to 4b. The most common zone, covering 297 of 395 ZIP codes, is 4a (−30 to −25°F average coldest winter night).

USDA hardiness zones in North Dakota

ZoneAvg. extreme minimumZIP codesExample cities
Zone 3b−35 to −30°F56—
Zone 4a−30 to −25°F297Fargo, Bismarck, Grand Forks, Minot
Zone 4b−25 to −20°F42Dickinson, Jamestown
 ZIP codes from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). Unpopulated areas such as high mountains can be colder than any ZIP code.

Growing zone and frost dates by city

CityZoneFrost dates
Fargo4a (−30 to −25°F)Fargo frost dates
Bismarck4a (−30 to −25°F)Bismarck frost dates
Grand Forks4a (−30 to −25°F)Grand Forks frost dates
Minot4a (−30 to −25°F)Minot frost dates
West Fargo4a (−30 to −25°F)West Fargo frost dates
Williston4a (−30 to −25°F)Williston frost dates
Dickinson4b (−25 to −20°F)Dickinson frost dates
Mandan4a (−30 to −25°F)Mandan frost dates
Jamestown4b (−25 to −20°F)Jamestown frost dates
Wahpeton4a (−30 to −25°F)Wahpeton frost dates
Devils Lake4a (−30 to −25°F)Devils Lake frost dates
Horace4a (−30 to −25°F)Horace frost dates
Valley City4a (−30 to −25°F)Valley City frost dates
Watford City4a (−30 to −25°F)Watford City frost dates
 Incorporated cities with 5,000+ residents. Each city uses the zone of its central ZIP code.

Frequently asked questions

What growing zone is North Dakota in?

North Dakota’s ZIP codes span USDA zones 3b to 4b, and 4a is the most common. Zones vary with elevation and distance from water, so check your own ZIP code.

When should I plant?

Hardiness zones are about winter cold, not planting dates. For timing, use the last spring frost date for your city on our North Dakota frost dates page.