Iowa planting zones & frost dates
USDA hardiness zones in Iowa go from 5a to 6a. Pick your city for its average frost dates and a planting calendar, or search by ZIP code.
| City | Zone | Avg. last frost | Avg. first frost |
|---|---|---|---|
| Altoona | 5b | Apr 21 | Oct 15 |
| Ames | 5b | Apr 26 | Oct 8 |
| Ankeny | 5b | Apr 23 | Oct 15 |
| Bettendorf | 5b | Apr 19 | Oct 22 |
| Boone | 5a | Apr 28 | Oct 12 |
| Burlington | 6a | Apr 15 | Oct 20 |
| Cedar Falls | 5a | Apr 27 | Oct 10 |
| Cedar Rapids | 5b | Apr 28 | Oct 12 |
| Clinton | 5b | Apr 13 | Oct 26 |
| Clive | 5b | Apr 18 | Oct 20 |
| Coralville | 5b | Apr 21 | Oct 18 |
| Council Bluffs | 6a | Apr 18 | Oct 21 |
| Davenport | 5b | Apr 19 | Oct 22 |
| Des Moines | 5b | Apr 18 | Oct 20 |
| Dubuque | 5a | Apr 19 | Oct 21 |
| Fort Dodge | 5a | Apr 28 | Oct 8 |
| Fort Madison | 6a | Apr 12 | Oct 25 |
| Grimes | 5b | Apr 19 | Oct 18 |
| Indianola | 5b | Apr 24 | Oct 12 |
| Iowa City | 5b | Apr 21 | Oct 18 |
| Johnston | 5b | Apr 19 | Oct 18 |
| Keokuk | 6a | Apr 10 | Oct 27 |
| Marion | 5a | Apr 28 | Oct 12 |
| Marshalltown | 5a | Apr 28 | Oct 7 |
| Mason City | 5a | Apr 29 | Oct 7 |
| Muscatine | 5b | Apr 18 | Oct 24 |
| Newton | 5b | Apr 22 | Oct 17 |
| North Liberty | 5b | Apr 21 | Oct 18 |
| Norwalk | 5b | Apr 18 | Oct 20 |
| Oskaloosa | 5b | Apr 21 | Oct 16 |
| Ottumwa | 5b | Apr 23 | Oct 14 |
| Pella | 5b | Apr 20 | Oct 19 |
| Sioux City | 5a | Apr 29 | Oct 7 |
| Spencer | 5a | May 1 | Oct 3 |
| Storm Lake | 5a | Apr 25 | Oct 13 |
| Urbandale | 5b | Apr 18 | Oct 20 |
| Waterloo | 5a | Apr 27 | Oct 10 |
| Waukee | 5b | Apr 19 | Oct 18 |
| Waverly | 5a | Apr 27 | Oct 10 |
| West Des Moines | 5b | Apr 18 | Oct 20 |
Cities with 10,000+ residents. Data: USDA Plant Hardiness Zone Map 2023 and NOAA Climate Normals 1991–2020. Sources and method.