When to plant Onion sets in Iowa
In spring, from Mar 1 – Apr 1 in Burlington to Mar 10 – Apr 1 in West Des Moines.
In fall: USDA's 1967 table lists onion sets as generally spring-planted in every place here. Newer advice from your state's extension service may differ.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring |
|---|---|
| Altoona | Mar 10 – Apr 1 |
| Ames | Mar 10 – Apr 10 |
| Ankeny | Mar 10 – Apr 1 |
| Bettendorf | Mar 10 – Apr 1 |
| Boone | Mar 10 – Apr 10 |
| Burlington | Mar 1 – Apr 1 |
| Carroll | Mar 10 – Apr 10 |
| Cedar Falls | Mar 10 – Apr 10 |
| Cedar Rapids | Mar 10 – Apr 10 |
| Clinton | Mar 10 – Apr 1 |
| Clive | Mar 10 – Apr 1 |
| Coralville | Mar 10 – Apr 1 |
| Council Bluffs | Mar 10 – Apr 1 |
| Davenport | Mar 10 – Apr 1 |
| Des Moines | Mar 10 – Apr 1 |
| Dubuque | Mar 10 – Apr 1 |
| Fort Dodge | Mar 10 – Apr 10 |
| Grimes | Mar 10 – Apr 1 |
| Indianola | Mar 10 – Apr 1 |
| Iowa City | Mar 10 – Apr 1 |
| Johnston | Mar 10 – Apr 1 |
| Le Mars | Mar 10 – Apr 10 |
| Marion | Mar 10 – Apr 10 |
| Marshalltown | Mar 10 – Apr 10 |
| Mason City | Mar 10 – Apr 10 |
| Muscatine | Mar 10 – Apr 1 |
| Newton | Mar 10 – Apr 1 |
| North Liberty | Mar 10 – Apr 1 |
| Norwalk | Mar 10 – Apr 1 |
| Oskaloosa | Mar 10 – Apr 1 |
| Ottumwa | Mar 10 – Apr 1 |
| Pella | Mar 10 – Apr 1 |
| Pleasant Hill | Mar 10 – Apr 1 |
| Sioux City | Mar 10 – Apr 10 |
| Spencer | Mar 10 – Apr 10 |
| Storm Lake | Mar 10 – Apr 1 |
| Urbandale | Mar 10 – Apr 1 |
| Waterloo | Mar 10 – Apr 10 |
| Waukee | Mar 10 – Apr 1 |
| Waverly | Mar 10 – Apr 10 |
| West Des Moines | Mar 10 – Apr 1 |
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for onion sets.