Union County, Ohio
Local growing conditions for Union County: the USDA hardiness zones found here, frost dates, and live weather for communities across the county. Based on 8 ZIP codes in our data.
Hardiness zones in Union County
Union County spans these USDA plant hardiness zones (by number of ZIP codes):
Local weather & frost dates
Open any community in Union County for its live forecast, frost dates, and planting calendar:
Raymond 43007
Magnetic Springs 43036
Marysville 43040
Milford Center 43045
Raymond 43067
Unionville Center 43077
Richwood 43344
West Mansfield 43358
More for Ohio
- Agriculture in Ohio
- Frost dates across Ohio
- 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.