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Best Counties for Cold-Hardy Crops

Published May 2, 2026

Cold-hardy crops — kale, Brussels sprouts, winter wheat, rye, and root vegetables — not only survive frost but often taste better after exposure to cold. These crops are essential for food security in the northern tier of the country, where the growing season is short but intense.

We identified the counties best suited for cold-hardy crop production, ranked by the coldest hardiness zones where winter adaptation is a way of life.

Best Counties for Cold-Hardy Crops

Beltrami County, MN in zone 3b with minimums of -35°F is a stronghold for cold-hardy agriculture.

RankCountyStateZoneMin Temp (°F)
1Beltrami CountyMN3b-35
2Clearwater CountyMN3b-35
3Cook CountyMN3b-35
4Hubbard CountyMN3b-35
5Itasca CountyMN3b-35
6Kittson CountyMN3b-35
7Koochiching CountyMN3b-35
8Lake CountyMN3b-35
9Lake of the Woods CountyMN3b-35
10Marshall CountyMN3b-35
11Pennington CountyMN3b-35
12Red Lake CountyMN3b-35
13Roseau CountyMN3b-35
14St. Louis CountyMN3b-35
15Daniels CountyMT3b-35
16Hill CountyMT3b-35
17Phillips CountyMT3b-35
18Sheridan CountyMT3b-35
19Bottineau CountyND3b-35
20Cavalier CountyND3b-35
21Pierce CountyND3b-35
22Rolette CountyND3b-35
23Towner CountyND3b-35
24Jackson CountyCO4b-25
25Howard CountyIA4b-25

Soil Management for Cold Climates

In cold zones, soil management focuses on extending the active season. Black plastic mulch warms soil in spring, cold frames and hoop houses add growing weeks, and heavy fall mulching protects soil biology from deep freezing. Building soil organic matter is critical — it acts as insulation and improves spring warm-up.

Methodology

Counties in USDA hardiness zones 5b and colder, ranked by lowest zone number. Data from USDA PHZM 2023.

Data sourced from USDA Plant Hardiness Zone Map (2023) and USDA SSURGO Soil Survey. Hardiness zone data represents average annual extreme minimum temperatures and should be used as a general guide. Local microclimates may vary significantly from county averages.

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