| 2023 Hardiness Zone: | Zone 7b: 5°F to 10°F Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 12a - Treasure Valley |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 83705 - Boise, ID | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 23 | 28 | 33 | 38 | 45 | 52 | 58 | 58 | 49 | 40 | 31 | 23 | 40 |
| Avg Max Temp (°F) | 37 | 44 | 54 | 62 | 71 | 81 | 89 | 88 | 78 | 65 | 48 | 37 | 63 |
| Avg Precip (In.) | 1.39 | 1.14 | 1.39 | 1.26 | 1.28 | .74 | .38 | .29 | .74 | .77 | 1.38 | 1.37 | 12.11 |