Frost dates in Boone County, Illinois
The average last spring frost in Boone County falls Apr 28 to May 1 and the average first fall frost Oct 10 to Oct 12, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 5b. Places: Belvidere, Capron, Garden Prairie, Loves Park, Poplar Grove. Pick a ZIP for 10% and 90% odds, soil temperature and the 7-day freeze forecast.
| ZIP | Place | Last spring frost | First fall frost | Zone |
|---|---|---|---|---|
| 61008 | Belvidere | Apr 28 | Oct 12 | 5b |
| 61011 | Loves Park | May 1 | Oct 12 | 5b |
| 61012 | Capron | Apr 30 | Oct 10 | 5b |
| 61038 | Garden Prairie | Apr 28 | Oct 12 | 5b |
| 61065 | Poplar Grove | Apr 30 | Oct 10 | 5b |
Nearby counties
Winnebago County McHenry County Ogle County DeKalb County Kane County Stephenson County
All Illinois counties · Download Illinois frost dates (CSV)
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