Washtenaw County, Michigan
Local growing conditions for Washtenaw County: the USDA hardiness zones found here, frost dates, and live weather for communities across the county. Based on 14 ZIP codes in our data.
Hardiness zones in Washtenaw County
Washtenaw County spans these USDA plant hardiness zones (by number of ZIP codes):
Local weather & frost dates
Open any community in Washtenaw County for its live forecast, frost dates, and planting calendar:
Ann Arbor 48108
Manchester 48158
Ann Arbor 48103
Ann Arbor 48104
Ann Arbor 48105
Ann Arbor 48109
Chelsea 48118
Dexter 48130
Saline 48176
Whitmore Lake 48189
Milan 48190
Milan 48191
Ypsilanti 48197
Ypsilanti 48198
More for Michigan
- Agriculture in Michigan
- Frost dates across Michigan
- 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.