Plymouth County, Iowa
Local growing conditions for Plymouth County: the USDA hardiness zones found here, frost dates, and live weather for communities across the county. Based on 11 ZIP codes in our data.
Hardiness zones in Plymouth County
Plymouth County spans these USDA plant hardiness zones (by number of ZIP codes):
Local weather & frost dates
Open any community in Plymouth County for its live forecast, frost dates, and planting calendar:
Akron 51001
Brunsville 51008
Hinton 51024
Kingsley 51028
Le Mars 51031
Merrill 51038
Oyens 51045
Remsen 51050
Westfield 51062
Sioux City 51108
Sioux City 51109
More for Iowa
- Agriculture in Iowa
- Frost dates across Iowa
- USDA hardiness zones explained
- Planting calendar by ZIP code
County growing conditions are compiled from our ZIP-code database, USDA hardiness-zone data, and NOAA climate normals. Conditions vary within a county by elevation and local microclimate. Page updated Aug 4, 2026.