Idaho planting zones & frost dates
The 3 Idaho cities on this site fall in zone 7a. Last spring frost dates range from Apr 30 in Boise to May 5 in Nampa.
| City | Zone | Last frost | First frost | Population |
|---|---|---|---|---|
| Boise | 7a | Apr 30 | Oct 14 | 237,963 |
| Meridian | 7a | May 5 | Oct 6 | 139,740 |
| Nampa | 7a | May 5 | Oct 6 | 117,350 |
Frost dates are 30%-risk dates from the nearest suitable NOAA station. Population: Census Vintage 2024 estimates.