When to plant Summer squash (zucchini) in Washington
In spring, from Mar 15 – May 1 in Anacortes to June 1 – 20 in Cheney.
In fall, from June 1 – Aug 10 in Aberdeen to June 10 – 20 in Cheney.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Aberdeen | Apr 10 – June 1 | June 1 – Aug 10 |
| Airway Heights | May 1 – 30 | June 1 – July 15 |
| Anacortes | Mar 15 – May 1 | June 1 – Aug 20 |
| Arlington | May 1 – June 15 | June 1 – July 20 |
| Auburn | Apr 1 – May 15 | June 1 – Aug 10 |
| Bainbridge Island | Apr 10 – June 1 | June 1 – Aug 10 |
| Battle Ground | May 1 – 30 | June 1 – July 20 |
| Bellevue | Mar 15 – May 1 | June 1 – Aug 20 |
| Bellingham | Apr 10 – June 1 | June 1 – Aug 1 |
| Bonney Lake | Apr 20 – June 1 | June 1 – Aug 1 |
| Bothell | Mar 15 – May 1 | June 1 – Aug 20 |
| Bremerton | Apr 10 – June 1 | June 1 – Aug 10 |
| Burien | Mar 15 – May 15 | June 1 – Aug 20 |
| Burlington | Apr 1 – May 15 | June 1 – Aug 1 |
| Camas | Apr 1 – May 15 | June 1 – Aug 20 |
| Centralia | May 1 – June 15 | June 1 – Aug 1 |
| Cheney | June 1 – 20 | June 10 – 20 |
| Covington | May 1 – June 15 | June 1 – July 20 |
| Des Moines | Mar 15 – May 15 | June 1 – Aug 20 |
| East Wenatchee | Apr 10 – June 1 | June 1 – Aug 1 |
| Edgewood | Mar 15 – May 1 | June 1 – Aug 10 |
| Edmonds | Mar 15 – May 1 | June 1 – Aug 20 |
| Ellensburg | May 10 – June 10 | June 1 – July 1 |
| Enumclaw | Apr 20 – June 1 | June 1 – Aug 1 |
| Everett | Apr 1 – May 15 | June 1 – Aug 1 |
| Federal Way | Mar 15 – May 1 | June 1 – Aug 10 |
| Ferndale | Apr 10 – June 1 | June 1 – Aug 1 |
| Fife | Mar 15 – May 1 | June 1 – Aug 10 |
| Gig Harbor | Mar 15 – May 1 | June 1 – Aug 20 |
| Grandview | May 1 – 30 | June 1 – July 15 |
| Issaquah | Mar 15 – May 1 | June 1 – Aug 20 |
| Kelso | Apr 20 – June 1 | June 1 – Aug 10 |
| Kenmore | Mar 15 – May 1 | June 1 – Aug 20 |
| Kennewick | Apr 10 – June 1 | June 1 – Aug 1 |
| Kent | Apr 1 – May 15 | June 1 – Aug 10 |
| Kirkland | Mar 15 – May 1 | June 1 – Aug 20 |
| Lacey | May 1 – 30 | June 1 – July 15 |
| Lake Forest Park | Mar 15 – May 1 | June 1 – Aug 20 |
| Lake Stevens | Apr 1 – May 15 | June 1 – Aug 1 |
| Lakewood | Mar 15 – May 1 | June 1 – Aug 20 |
| Liberty Lake | May 1 – 30 | June 1 – July 15 |
| Longview | Apr 20 – June 1 | June 1 – Aug 10 |
| Lynden | May 1 – June 15 | June 1 – July 20 |
| Lynnwood | Mar 15 – May 1 | June 1 – Aug 20 |
| Maple Valley | May 1 – June 15 | June 1 – July 20 |
| Marysville | Apr 1 – May 15 | June 1 – Aug 1 |
| Mercer Island | Mar 15 – May 1 | June 1 – Aug 20 |
| Mill Creek | Mar 15 – May 1 | June 1 – Aug 20 |
| Monroe | May 1 – June 15 | June 1 – July 20 |
| Moses Lake | May 1 – 30 | June 1 – July 15 |
| Mount Vernon | Apr 1 – May 15 | June 1 – Aug 1 |
| Mountlake Terrace | Mar 15 – May 1 | June 1 – Aug 20 |
| Mukilteo | Mar 15 – May 1 | June 1 – Aug 20 |
| Newcastle | Mar 15 – May 1 | June 1 – Aug 20 |
| Oak Harbor | Mar 15 – May 1 | June 1 – Aug 10 |
| Olympia | May 1 – 30 | June 1 – July 15 |
| Pasco | May 1 – 30 | June 1 – July 15 |
| Port Angeles | Mar 15 – May 1 | June 1 – Aug 20 |
| Port Orchard | Apr 10 – June 1 | June 1 – Aug 10 |
| Port Townsend | Mar 15 – May 15 | June 1 – Sept 1 |
| Poulsbo | Apr 10 – June 1 | June 1 – Aug 10 |
| Pullman | May 10 – June 10 | June 1 – July 1 |
| Puyallup | Apr 20 – June 1 | June 1 – Aug 1 |
| Redmond | Mar 15 – May 1 | June 1 – Aug 20 |
| Renton | Mar 15 – May 1 | June 1 – Aug 20 |
| Richland | Apr 20 – June 1 | June 1 – July 20 |
| Ridgefield | May 1 – 30 | June 1 – July 20 |
| Sammamish | Apr 10 – June 1 | June 1 – Aug 10 |
| SeaTac | Mar 15 – May 15 | June 1 – Aug 20 |
| Seattle | Mar 15 – May 1 | June 1 – Aug 20 |
| Sedro-Woolley | Apr 10 – June 1 | June 1 – Aug 10 |
| Shelton | May 1 – 30 | June 1 – July 20 |
| Shoreline | Mar 15 – May 1 | June 1 – Aug 20 |
| Snohomish | Apr 1 – May 15 | June 1 – Aug 1 |
| Snoqualmie | Apr 10 – June 1 | June 1 – Aug 10 |
| Spokane | May 1 – 30 | June 1 – July 15 |
| Spokane Valley | May 1 – 30 | June 1 – July 15 |
| Sumner | Apr 20 – June 1 | June 1 – Aug 1 |
| Sunnyside | May 1 – 30 | June 1 – July 15 |
| Tacoma | Mar 15 – May 1 | June 1 – Aug 10 |
| Tukwila | Mar 15 – May 15 | June 1 – Aug 20 |
| Tumwater | May 1 – 30 | June 1 – July 15 |
| University Place | Mar 15 – May 1 | June 1 – Aug 20 |
| Vancouver | Apr 10 – June 1 | June 1 – Aug 10 |
| Walla Walla | Apr 10 – June 1 | June 1 – Aug 1 |
| Washougal | Apr 10 – June 1 | June 1 – Aug 20 |
| Wenatchee | Apr 10 – June 1 | June 1 – Aug 1 |
| West Richland | Apr 20 – June 1 | June 1 – July 20 |
| Woodinville | Mar 15 – May 1 | June 1 – Aug 20 |
| Yakima | Apr 20 – June 1 | June 1 – July 20 |
| Yelm | May 1 – 30 | June 1 – July 15 |
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.