When to plant Summer squash (zucchini) in Illinois
In spring, from Apr 10 – June 1 in Alton to May 1 – 30 in Zion.
In fall, June 1 – Aug 1.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Addison | May 1 – June 15 | June 1 – Aug 1 |
| Algonquin | May 1 – 30 | June 1 – July 20 |
| Alsip | Apr 20 – June 1 | June 1 – Aug 1 |
| Alton | Apr 10 – June 1 | June 1 – Aug 10 |
| Antioch | May 1 – June 15 | June 1 – July 20 |
| Arlington Heights | May 1 – June 15 | June 1 – Aug 1 |
| Aurora | May 1 – June 15 | June 1 – July 20 |
| Barrington | May 1 – June 15 | June 1 – July 20 |
| Bartlett | May 1 – 30 | June 1 – July 15 |
| Batavia | May 1 – June 15 | June 1 – July 20 |
| Beach Park | May 1 – 30 | June 1 – July 20 |
| Belleville | Apr 20 – June 1 | June 1 – July 20 |
| Bellwood | May 1 – June 15 | June 1 – Aug 1 |
| Belvidere | May 1 – June 15 | June 1 – July 20 |
| Bensenville | May 1 – June 15 | June 1 – Aug 1 |
| Berwyn | Apr 20 – June 1 | June 1 – Aug 1 |
| Bloomingdale | May 1 – 30 | June 1 – July 15 |
| Bloomington | May 1 – June 15 | June 1 – July 20 |
| Blue Island | Apr 20 – June 1 | June 1 – Aug 1 |
| Bolingbrook | May 1 – June 15 | June 1 – July 20 |
| Bourbonnais | May 1 – June 15 | June 1 – July 20 |
| Bradley | May 1 – June 15 | June 1 – July 20 |
| Bridgeview | Apr 20 – June 1 | June 1 – Aug 1 |
| Brookfield | Apr 20 – June 1 | June 1 – Aug 1 |
| Buffalo Grove | May 1 – June 15 | June 1 – Aug 1 |
| Burbank | Apr 20 – June 1 | June 1 – Aug 1 |
| Burr Ridge | May 1 – June 15 | June 1 – July 20 |
| Cahokia Heights | Apr 20 – June 1 | June 1 – Aug 1 |
| Calumet City | May 1 – June 15 | June 1 – July 20 |
| Campton Hills | May 1 – June 15 | June 1 – July 20 |
| Canton | May 1 – June 15 | June 1 – July 20 |
| Carbondale | Apr 20 – June 1 | June 1 – July 20 |
| Carol Stream | May 1 – June 15 | June 1 – July 20 |
| Carpentersville | May 1 – 30 | June 1 – July 20 |
| Cary | May 1 – 30 | June 1 – July 15 |
| Centralia | Apr 20 – June 1 | June 1 – July 20 |
| Champaign | Apr 20 – June 1 | June 1 – July 20 |
| Channahon | May 1 – June 15 | June 1 – Aug 1 |
| Charleston | Apr 20 – June 1 | June 1 – July 20 |
| Chatham | Apr 20 – June 1 | June 1 – July 20 |
| Chicago | Apr 20 – June 1 | June 1 – Aug 10 |
| Chicago Heights | May 1 – June 15 | June 1 – July 20 |
| Chicago Ridge | Apr 20 – June 1 | June 1 – Aug 1 |
| Cicero | Apr 20 – June 1 | June 1 – Aug 1 |
| Collinsville | Apr 20 – June 1 | June 1 – Aug 1 |
| Columbia | Apr 20 – June 1 | June 1 – Aug 1 |
| Country Club Hills | May 1 – June 15 | June 1 – July 20 |
| Crest Hill | May 1 – June 15 | June 1 – July 20 |
| Crestwood | Apr 20 – June 1 | June 1 – Aug 1 |
| Crystal Lake | May 1 – June 15 | June 1 – July 20 |
| Danville | May 1 – June 15 | June 1 – July 20 |
| Darien | May 1 – June 15 | June 1 – July 20 |
| Decatur | Apr 20 – June 1 | June 1 – July 20 |
| Deerfield | May 1 – 30 | June 1 – July 20 |
| DeKalb | May 1 – June 15 | June 1 – July 20 |
| Des Plaines | May 1 – June 15 | June 1 – Aug 1 |
| Dixon | May 1 – June 15 | June 1 – July 20 |
| Dolton | May 1 – June 15 | June 1 – July 20 |
| Downers Grove | May 1 – 30 | June 1 – July 20 |
| East Moline | May 1 – June 15 | June 1 – July 20 |
| East Peoria | May 1 – June 15 | June 1 – July 20 |
| East St. Louis | Apr 20 – June 1 | June 1 – Aug 1 |
| Edwardsville | Apr 10 – June 1 | June 1 – Aug 10 |
| Effingham | Apr 20 – June 1 | June 1 – July 20 |
| Elgin | May 1 – 30 | June 1 – July 20 |
| Elk Grove Village | May 1 – June 15 | June 1 – Aug 1 |
| Elmhurst | May 1 – June 15 | June 1 – Aug 1 |
| Elmwood Park | May 1 – June 15 | June 1 – Aug 1 |
| Evanston | May 1 – 30 | June 1 – July 20 |
| Evergreen Park | Apr 20 – June 1 | June 1 – Aug 1 |
| Fairview Heights | Apr 20 – June 1 | June 1 – Aug 1 |
| Forest Park | Apr 20 – June 1 | June 1 – Aug 1 |
| Fox Lake | May 1 – June 15 | June 1 – July 20 |
| Frankfort | May 1 – June 15 | June 1 – July 20 |
| Franklin Park | May 1 – June 15 | June 1 – Aug 1 |
| Freeport | May 1 – 30 | June 1 – July 15 |
| Galesburg | May 1 – June 15 | June 1 – July 20 |
| Geneva | May 1 – June 15 | June 1 – July 20 |
| Glen Carbon | Apr 10 – June 1 | June 1 – Aug 10 |
| Glen Ellyn | May 1 – 30 | June 1 – July 20 |
| Glendale Heights | May 1 – 30 | June 1 – July 20 |
| Glenview | May 1 – 30 | June 1 – July 20 |
| Godfrey | Apr 10 – June 1 | June 1 – Aug 10 |
| Granite City | Apr 10 – June 1 | June 1 – Aug 10 |
| Grayslake | May 1 – 30 | June 1 – July 20 |
| Gurnee | May 1 – 30 | June 1 – July 20 |
| Hanover Park | May 1 – 30 | June 1 – July 15 |
| Harvey | May 1 – June 15 | June 1 – July 20 |
| Hazel Crest | May 1 – June 15 | June 1 – July 20 |
| Herrin | Apr 20 – June 1 | June 1 – July 20 |
| Hickory Hills | May 1 – June 15 | June 1 – July 20 |
| Highland | Apr 20 – June 1 | June 1 – July 20 |
| Highland Park | May 1 – 30 | June 1 – July 20 |
| Hinsdale | May 1 – June 15 | June 1 – July 20 |
| Hoffman Estates | May 1 – 30 | June 1 – July 15 |
| Homer Glen | May 1 – June 15 | June 1 – July 20 |
| Homewood | May 1 – June 15 | June 1 – July 20 |
| Huntley | May 1 – June 15 | June 1 – July 20 |
| Jacksonville | May 1 – June 15 | June 1 – July 20 |
| Joliet | May 1 – June 15 | June 1 – July 20 |
| Justice | Apr 20 – June 1 | June 1 – Aug 1 |
| Kankakee | May 1 – June 15 | June 1 – July 20 |
| Kewanee | May 1 – June 15 | June 1 – July 20 |
| La Grange | Apr 20 – June 1 | June 1 – Aug 1 |
| La Grange Park | Apr 20 – June 1 | June 1 – Aug 1 |
| Lake Forest | May 1 – 30 | June 1 – July 20 |
| Lake in the Hills | May 1 – June 15 | June 1 – July 20 |
| Lake Zurich | May 1 – 30 | June 1 – July 20 |
| Lansing | May 1 – June 15 | June 1 – July 20 |
| Lemont | May 1 – June 15 | June 1 – July 20 |
| Libertyville | May 1 – 30 | June 1 – July 20 |
| Lincoln | May 1 – June 15 | June 1 – July 20 |
| Lincolnwood | May 1 – 30 | June 1 – July 20 |
| Lindenhurst | May 1 – June 15 | June 1 – July 20 |
| Lisle | May 1 – 30 | June 1 – July 20 |
| Lockport | May 1 – June 15 | June 1 – July 20 |
| Lombard | May 1 – 30 | June 1 – July 20 |
| Loves Park | May 1 – June 15 | June 1 – July 20 |
| Lyons | Apr 20 – June 1 | June 1 – Aug 1 |
| Machesney Park | May 1 – 30 | June 1 – July 15 |
| Macomb | May 1 – June 15 | June 1 – July 20 |
| Mahomet | May 1 – June 15 | June 1 – July 15 |
| Manhattan | May 1 – June 15 | June 1 – July 20 |
| Marion | Apr 20 – June 1 | June 1 – July 20 |
| Markham | May 1 – June 15 | June 1 – July 20 |
| Matteson | May 1 – June 15 | June 1 – July 20 |
| Mattoon | Apr 20 – June 1 | June 1 – Aug 1 |
| Maywood | Apr 20 – June 1 | June 1 – Aug 1 |
| McHenry | May 1 – 30 | June 1 – July 15 |
| Melrose Park | May 1 – June 15 | June 1 – Aug 1 |
| Midlothian | Apr 20 – June 1 | June 1 – Aug 1 |
| Minooka | May 1 – June 15 | June 1 – Aug 1 |
| Mokena | May 1 – June 15 | June 1 – July 20 |
| Moline | May 1 – June 15 | June 1 – July 20 |
| Montgomery | May 1 – June 15 | June 1 – July 20 |
| Morris | May 1 – June 15 | June 1 – July 20 |
| Morton | May 1 – June 15 | June 1 – July 20 |
| Morton Grove | May 1 – 30 | June 1 – July 20 |
| Mount Prospect | May 1 – June 15 | June 1 – Aug 1 |
| Mount Vernon | Apr 20 – June 1 | June 1 – July 20 |
| Mundelein | May 1 – 30 | June 1 – July 20 |
| Naperville | May 1 – 30 | June 1 – July 20 |
| New Lenox | May 1 – June 15 | June 1 – July 20 |
| Niles | May 1 – June 15 | June 1 – Aug 1 |
| Normal | May 1 – June 15 | June 1 – July 20 |
| Norridge | May 1 – June 15 | June 1 – Aug 1 |
| North Aurora | May 1 – June 15 | June 1 – July 20 |
| North Chicago | May 1 – 30 | June 1 – July 20 |
| Northbrook | May 1 – 30 | June 1 – July 20 |
| Northlake | May 1 – June 15 | June 1 – Aug 1 |
| O'Fallon | Apr 20 – June 1 | June 1 – July 20 |
| Oak Forest | May 1 – June 15 | June 1 – July 20 |
| Oak Lawn | Apr 20 – June 1 | June 1 – Aug 1 |
| Oak Park | Apr 20 – June 1 | June 1 – Aug 1 |
| Orland Park | May 1 – June 15 | June 1 – July 20 |
| Oswego | May 1 – June 15 | June 1 – July 20 |
| Ottawa | May 1 – 30 | June 1 – July 20 |
| Palatine | May 1 – June 15 | June 1 – July 20 |
| Palos Heights | Apr 20 – June 1 | June 1 – Aug 1 |
| Palos Hills | May 1 – June 15 | June 1 – July 20 |
| Park Forest | May 1 – June 15 | June 1 – July 20 |
| Park Ridge | May 1 – June 15 | June 1 – Aug 1 |
| Pekin | May 1 – June 15 | June 1 – July 20 |
| Peoria | May 1 – June 15 | June 1 – July 20 |
| Pingree Grove | May 1 – 30 | June 1 – July 20 |
| Plainfield | May 1 – June 15 | June 1 – July 20 |
| Plano | May 1 – 30 | June 1 – July 15 |
| Pontiac | May 1 – June 15 | June 1 – July 20 |
| Prospect Heights | May 1 – June 15 | June 1 – Aug 1 |
| Quincy | Apr 20 – June 1 | June 1 – Aug 1 |
| Rantoul | May 1 – June 15 | June 1 – July 20 |
| Richton Park | May 1 – June 15 | June 1 – July 20 |
| River Forest | Apr 20 – June 1 | June 1 – Aug 1 |
| River Grove | May 1 – June 15 | June 1 – Aug 1 |
| Riverdale | Apr 20 – June 1 | June 1 – Aug 1 |
| Rock Island | May 1 – June 15 | June 1 – July 20 |
| Rockford | May 1 – June 15 | June 1 – July 20 |
| Rolling Meadows | May 1 – June 15 | June 1 – Aug 1 |
| Romeoville | May 1 – June 15 | June 1 – July 20 |
| Roscoe | May 1 – 30 | June 1 – July 15 |
| Roselle | May 1 – 30 | June 1 – July 15 |
| Round Lake | May 1 – 30 | June 1 – July 20 |
| Round Lake Beach | May 1 – June 15 | June 1 – July 20 |
| Schaumburg | May 1 – 30 | June 1 – July 15 |
| Schiller Park | May 1 – June 15 | June 1 – Aug 1 |
| Shiloh | Apr 20 – June 1 | June 1 – July 20 |
| Shorewood | May 1 – June 15 | June 1 – July 20 |
| Skokie | May 1 – 30 | June 1 – July 20 |
| South Elgin | May 1 – 30 | June 1 – July 20 |
| South Holland | May 1 – June 15 | June 1 – July 20 |
| Springfield | Apr 20 – June 1 | June 1 – July 20 |
| St. Charles | May 1 – June 15 | June 1 – July 20 |
| Sterling | May 1 – June 15 | June 1 – July 20 |
| Streamwood | May 1 – 30 | June 1 – July 15 |
| Streator | Apr 20 – June 1 | June 1 – Aug 1 |
| Summit | Apr 20 – June 1 | June 1 – Aug 1 |
| Swansea | Apr 20 – June 1 | June 1 – July 20 |
| Sycamore | May 1 – June 15 | June 1 – July 20 |
| Taylorville | Apr 20 – June 1 | June 1 – July 20 |
| Tinley Park | May 1 – June 15 | June 1 – July 20 |
| Troy | Apr 20 – June 1 | June 1 – July 20 |
| Urbana | Apr 20 – June 1 | June 1 – July 20 |
| Vernon Hills | May 1 – 30 | June 1 – July 20 |
| Villa Park | May 1 – 30 | June 1 – July 20 |
| Warrenville | May 1 – 30 | June 1 – July 20 |
| Washington | May 1 – June 15 | June 1 – July 20 |
| Waterloo | Apr 20 – June 1 | June 1 – Aug 1 |
| Wauconda | May 1 – 30 | June 1 – July 20 |
| Waukegan | May 1 – 30 | June 1 – July 20 |
| West Chicago | May 1 – June 15 | June 1 – July 20 |
| Westchester | Apr 20 – June 1 | June 1 – Aug 1 |
| Western Springs | May 1 – June 15 | June 1 – July 20 |
| Westmont | May 1 – 30 | June 1 – July 20 |
| Wheaton | May 1 – 30 | June 1 – July 20 |
| Wheeling | May 1 – June 15 | June 1 – Aug 1 |
| Wilmette | May 1 – 30 | June 1 – July 20 |
| Winfield | May 1 – June 15 | June 1 – July 20 |
| Winnetka | May 1 – 30 | June 1 – July 20 |
| Wood Dale | May 1 – June 15 | June 1 – Aug 1 |
| Wood River | Apr 10 – June 1 | June 1 – Aug 10 |
| Woodridge | May 1 – 30 | June 1 – July 20 |
| Woodstock | May 1 – June 15 | June 1 – July 20 |
| Worth | Apr 20 – June 1 | June 1 – Aug 1 |
| Yorkville | May 1 – 30 | June 1 – July 15 |
| Zion | May 1 – 30 | 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.