Frost dates in Boise County, Idaho
The average last spring frost in Boise County falls May 17 to Jun 17 and the average first fall frost Sep 4 to Oct 12, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 6a to 7a. Places: Banks, Garden Valley, Horseshoe Bend, Idaho City, Lowman, Placerville. 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 |
|---|---|---|---|---|
| 83602 | Banks | Jun 1 | Sep 10 | 7a |
| 83622 | Garden Valley | Jun 1 | Sep 10 | 6b |
| 83629 | Horseshoe Bend | May 17 | Oct 12 | 7a |
| 83631 | Idaho City | Jun 17 | Sep 5 | 6b |
| 83637 | Lowman | Jun 6 | Sep 4 | 6a |
| 83666 | Placerville | Jun 1 | Sep 10 | 6b |
Nearby counties
Gem County Ada County Payette County Canyon County Elmore County Washington County
All Idaho counties · Download Idaho frost dates (CSV)
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