When to plant Summer squash (zucchini) in Iowa
In spring, from Apr 20 – June 1 in Burlington to May 1 – June 15 in West Des Moines.
In fall, June 1 – July 15.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Altoona | May 1 – June 15 | June 1 – July 15 |
| Ames | May 1 – 30 | June 1 – July 15 |
| Ankeny | May 1 – June 15 | June 1 – July 15 |
| Bettendorf | May 1 – June 15 | June 1 – July 20 |
| Boone | May 1 – 30 | June 1 – July 15 |
| Burlington | Apr 20 – June 1 | June 1 – July 20 |
| Carroll | May 1 – 30 | June 1 – July 15 |
| Cedar Falls | May 1 – 30 | June 1 – July 15 |
| Cedar Rapids | May 1 – 30 | June 1 – July 15 |
| Clinton | May 1 – June 15 | June 1 – July 20 |
| Clive | May 1 – June 15 | June 1 – July 20 |
| Coralville | May 1 – June 15 | June 1 – July 20 |
| Council Bluffs | May 1 – June 15 | June 1 – July 20 |
| Davenport | May 1 – June 15 | June 1 – July 20 |
| Des Moines | May 1 – June 15 | June 1 – July 20 |
| Dubuque | May 1 – June 15 | June 1 – July 20 |
| Fort Dodge | May 1 – 30 | June 1 – July 15 |
| Grimes | May 1 – June 15 | June 1 – July 20 |
| Indianola | May 1 – June 15 | June 1 – July 15 |
| Iowa City | May 1 – June 15 | June 1 – July 20 |
| Johnston | May 1 – June 15 | June 1 – July 20 |
| Le Mars | May 1 – 30 | June 1 – July 1 |
| Marion | May 1 – 30 | June 1 – July 15 |
| Marshalltown | May 1 – 30 | June 1 – July 15 |
| Mason City | May 1 – 30 | June 1 – July 15 |
| Muscatine | May 1 – June 15 | June 1 – July 15 |
| Newton | May 1 – June 15 | June 1 – July 20 |
| North Liberty | May 1 – June 15 | June 1 – July 20 |
| Norwalk | May 1 – June 15 | June 1 – July 20 |
| Oskaloosa | May 1 – June 15 | June 1 – July 20 |
| Ottumwa | May 1 – June 15 | June 1 – July 15 |
| Pella | May 1 – June 15 | June 1 – July 20 |
| Pleasant Hill | May 1 – June 15 | June 1 – July 20 |
| Sioux City | May 1 – 30 | June 1 – July 15 |
| Spencer | May 1 – 30 | June 1 – July 1 |
| Storm Lake | May 1 – June 15 | June 1 – July 15 |
| Urbandale | May 1 – June 15 | June 1 – July 20 |
| Waterloo | May 1 – 30 | June 1 – July 15 |
| Waukee | May 1 – June 15 | June 1 – July 20 |
| Waverly | May 1 – 30 | June 1 – July 15 |
| West Des Moines | May 1 – June 15 | June 1 – July 20 |
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 summer squash.