South Dakota planting zones & frost dates
The 2 South Dakota cities on this site fall in zone 5a. Last spring frost dates range from May 6 in Sioux Falls to May 9 in Rapid City.
| City | Zone | Last frost | First frost | Population |
|---|---|---|---|---|
| Sioux Falls | 5a | May 6 | Sep 30 | 209,289 |
| Rapid City | 5a | May 9 | Oct 1 | 79,894 |
Frost dates are 30%-risk dates from the nearest suitable NOAA station. Population: Census Vintage 2024 estimates.