Frost dates · 9 cities · zones 5b–7a
Idaho frost dates, city by city
Median last spring frost across 9 Idaho cities runs from April 22 in Coeur d'Alene to May 9 in Idaho Falls.
| City | Zone | Last frost median | First frost median | Season | Jan → Dec |
|---|---|---|---|---|---|
| Boise | 7a | Apr 24 | Oct 21 | 179 d | |
| Meridian | 7a | Apr 24 | Oct 21 | 179 d | |
| Nampa | 7a | Apr 29 | Oct 13 | 164 d | |
| Caldwell | 7a | Apr 29 | Oct 13 | 164 d | |
| Idaho Falls | 5b | May 9 | Oct 1 | 142 d | |
| Pocatello | 6a | May 2 | Oct 11 | 161 d | |
| Coeur d'Alene | 6b | Apr 22 | Oct 18 | 179 d | |
| Twin Falls | 7a | Apr 25 | Oct 15 | 172 d | |
| Post Falls | 6b | Apr 22 | Oct 18 | 179 d |
Medians from NOAA NCEI 1991–2020 U.S. Climate Normals at each city's nearest qualifying station; zones from the 2023 USDA Plant Hardiness Zone Map. Open a city for the 1-in-10-year dates, the station, and a planting calendar for every sauce crop.
All states →Build a plan from your ZIP →Earliest: Coeur d'Alene (Apr 22) · Latest: Idaho Falls (May 9)