When to plant Summer squash (zucchini) in Pennsylvania
In spring, from Apr 10 – June 1 in Chester to May 10 – June 10 in St. Marys.
In fall, June 1 – July 20.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Allentown | May 1 – June 15 | June 1 – July 20 |
| Altoona | May 1 – June 15 | June 1 – July 20 |
| Baldwin | May 1 – June 15 | June 1 – Aug 1 |
| Berwick | May 1 – 30 | June 1 – July 15 |
| Bethel Park | May 1 – June 15 | June 1 – Aug 1 |
| Bethlehem | May 1 – June 15 | June 1 – July 20 |
| Bloomsburg | May 1 – 30 | June 1 – July 20 |
| Butler | May 10 – June 10 | June 1 – July 15 |
| Carlisle | May 1 – June 15 | June 1 – July 20 |
| Chambersburg | May 1 – June 15 | June 1 – July 20 |
| Chester | Apr 10 – June 1 | June 1 – Aug 20 |
| Coatesville | May 1 – June 15 | June 1 – July 20 |
| Columbia | May 1 – 30 | June 1 – July 15 |
| Darby | Apr 10 – June 1 | June 1 – Aug 10 |
| Dunmore | May 1 – June 15 | June 1 – July 20 |
| Easton | May 1 – June 15 | June 1 – July 20 |
| Elizabethtown | Apr 20 – June 1 | June 1 – Aug 1 |
| Emmaus | May 1 – June 15 | June 1 – July 20 |
| Ephrata | May 1 – June 15 | June 1 – July 20 |
| Erie | May 1 – 30 | June 1 – Aug 1 |
| Franklin Park | May 1 – June 15 | June 1 – Aug 1 |
| Greensburg | May 1 – 30 | June 1 – July 15 |
| Hanover | May 1 – June 15 | June 1 – July 20 |
| Harrisburg | Apr 20 – June 1 | June 1 – July 20 |
| Hazleton | May 1 – 30 | June 1 – July 20 |
| Hermitage | May 10 – June 10 | June 1 – July 1 |
| Indiana | May 10 – June 10 | June 1 – July 15 |
| Jefferson Hills | May 1 – June 15 | June 1 – Aug 1 |
| Johnstown | May 1 – 30 | June 1 – July 20 |
| Kingston | May 1 – June 15 | June 1 – July 20 |
| Lancaster | May 1 – June 15 | June 1 – July 20 |
| Lansdale | Apr 20 – June 1 | June 1 – Aug 1 |
| Lansdowne | Apr 10 – June 1 | June 1 – Aug 10 |
| Lebanon | May 1 – June 15 | June 1 – July 20 |
| Lower Burrell | May 1 – June 15 | June 1 – Aug 1 |
| McKeesport | May 1 – 30 | June 1 – July 20 |
| Meadville | May 1 – 30 | June 1 – July 20 |
| Mechanicsburg | Apr 20 – June 1 | June 1 – Aug 1 |
| Monroeville | May 1 – June 15 | June 1 – July 20 |
| Munhall | Apr 20 – June 1 | June 1 – Aug 10 |
| Murrysville | May 1 – June 15 | June 1 – July 20 |
| Nanticoke | May 10 – June 10 | June 1 – July 15 |
| New Castle | May 1 – 30 | June 1 – July 20 |
| New Kensington | May 1 – June 15 | June 1 – Aug 1 |
| Norristown | Apr 20 – June 1 | June 1 – Aug 1 |
| Northampton | May 1 – June 15 | June 1 – July 20 |
| Philadelphia | Apr 10 – June 1 | June 1 – Aug 20 |
| Phoenixville | May 1 – June 15 | June 1 – Aug 1 |
| Pittsburgh | May 1 – June 15 | June 1 – Aug 1 |
| Plum | May 1 – June 15 | June 1 – Aug 1 |
| Pottstown | May 1 – June 15 | June 1 – July 20 |
| Pottsville | May 1 – 30 | June 1 – July 20 |
| Reading | Apr 20 – June 1 | June 1 – Aug 1 |
| Scranton | May 1 – June 15 | June 1 – July 20 |
| Sharon | May 1 – 30 | June 1 – July 20 |
| St. Marys | May 10 – June 10 | June 1 – July 15 |
| State College | May 1 – June 15 | June 1 – Aug 1 |
| Washington | May 1 – June 15 | June 1 – July 20 |
| Waynesboro | May 1 – June 15 | June 1 – July 20 |
| West Chester | May 1 – 30 | June 1 – July 20 |
| West Mifflin | May 1 – June 15 | June 1 – Aug 1 |
| Whitehall | May 1 – June 15 | June 1 – Aug 1 |
| Wilkes-Barre | May 1 – June 15 | June 1 – July 20 |
| Wilkinsburg | Apr 20 – June 1 | June 1 – Aug 10 |
| Williamsport | May 1 – June 15 | June 1 – July 20 |
| Wyomissing | Apr 20 – June 1 | June 1 – Aug 1 |
| Yeadon | Apr 10 – June 1 | June 1 – Aug 10 |
| York | 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.