Winnebago County, Illinois
Local growing conditions for Winnebago County: the USDA hardiness zones found here, frost dates, and live weather for communities across the county. Based on 20 ZIP codes in our data.
Hardiness zones in Winnebago County
Winnebago County spans these USDA plant hardiness zones (by number of ZIP codes):
Local weather & frost dates
Open any community in Winnebago County for its live forecast, frost dates, and planting calendar:
Cherry Valley 61016
Durand 61024
Pecatonica 61063
Rockton 61072
Roscoe 61073
Pecatonica 61077
Durand 61079
South Beloit 61080
Winnebago 61088
Rockford 61101
Rockford 61102
Rockford 61103
Rockford 61104
Rockford 61107
Rockford 61108
New Milford 61109
Loves Park 61111
Cherry Valley 61112
Rockford 61114
Machesney Park 61115
More for Illinois
- Agriculture in Illinois
- Frost dates across Illinois
- 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.