When to plant sweet corn in Washington
Washington spans USDA zones 6b–9a, so the right time to plant sweet corn shifts by weeks across the state. The window to sow seed directly outdoors runs from about March 1 in Port Townsend to May 30 in Cheney — below are local dates for 132 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Seattle | 9a | March 8 | November 23 | March 8 – March 22 |
| Spokane | 7a | April 26 | October 15 | April 26 – May 10 |
| Tacoma | 8b | March 8 | November 14 | March 8 – March 22 |
| Vancouver | 8b | March 29 | November 9 | March 29 – April 12 |
| Bellevue | 9a | March 8 | November 23 | March 8 – March 22 |
| Kent | 8b | March 20 | November 10 | March 20 – April 3 |
| Everett | 8b | March 24 | November 2 | March 24 – April 7 |
| Spokane Valley | 7a | April 26 | October 15 | April 26 – May 10 |
Sweet Corn in Washington: FAQ
When can I plant sweet corn in Washington?
Across Washington, the time to direct-sow sweet corn spans roughly March 1 in Port Townsend to May 30 in Cheney, each following that city's local frost dates.
Does the sweet corn planting date vary across Washington?
Yes. Washington publishes 132 cities with their own frost dates, so the right sweet corn planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
How long does sweet corn take to grow in Washington?
Sweet Corn takes about 60–90 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.
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