When to plant sunflower in Wisconsin
Wisconsin spans USDA zones 4b–6a, so the right time to plant sunflower shifts by weeks across the state. The window to sow seed directly outdoors runs from about April 19 in Pleasant Prairie to May 11 in River Falls — below are local dates for 97 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Milwaukee | 6a | April 26 | October 18 | April 26 – May 17 |
| Madison | 5a | May 1 | October 9 | May 1 – May 22 |
| Green Bay | 5b | May 7 | October 9 | May 7 – May 28 |
| Kenosha | 5b | April 28 | October 19 | April 28 – May 19 |
| Racine | 6a | April 20 | October 24 | April 20 – May 11 |
| Appleton | 5b | May 4 | October 6 | May 4 – May 25 |
| Waukesha | 5b | May 1 | October 13 | May 1 – May 22 |
| Eau Claire | 4b | April 24 | October 14 | April 24 – May 15 |
Sunflower in Wisconsin: FAQ
When can I plant sunflower in Wisconsin?
Across Wisconsin, the time to direct-sow sunflower spans roughly April 19 in Pleasant Prairie to May 11 in River Falls, each following that city's local frost dates.
Does the sunflower planting date vary across Wisconsin?
Yes. Wisconsin publishes 97 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 Wisconsin?
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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