When to plant sunflower in Delaware
Delaware spans USDA zones 7a–7b, so the right time to plant sunflower shifts by weeks across the state. The window to sow seed directly outdoors runs from about April 4 in Dover to April 11 in Milford — below are local dates for 11 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Wilmington | 7b | April 7 | November 4 | April 7 – April 28 |
| Dover | 7b | April 4 | November 4 | April 4 – April 25 |
| Newark | 7b | April 7 | November 2 | April 7 – April 28 |
| Middletown | 7b | April 7 | November 2 | April 7 – April 28 |
| Bear | 7b | April 7 | November 2 | April 7 – April 28 |
| Glasgow | 7b | April 7 | November 2 | April 7 – April 28 |
| Brookside | 7b | April 7 | November 2 | April 7 – April 28 |
| Hockessin | 7a | April 7 | November 4 | April 7 – April 28 |
Sunflower in Delaware: FAQ
When can I plant sunflower in Delaware?
Across Delaware, the time to direct-sow sunflower spans roughly April 4 in Dover to April 11 in Milford, each following that city's local frost dates.
Does the sunflower planting date vary across Delaware?
Yes. Delaware publishes 11 cities with their own frost dates, so the right sunflower 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 sunflower take to grow in Delaware?
Sunflower takes about 70–100 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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