When to plant acorn squash in South Dakota
South Dakota spans USDA zones 4a–5b, so the right time to plant acorn squash shifts by weeks across the state. The window to sow seed directly outdoors runs from about May 3 in Sioux Falls to May 19 in Spearfish — below are local dates for 13 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Sioux Falls | 5a | April 26 | October 13 | May 3 – May 17 |
| Rapid City | 5b | May 3 | October 8 | May 10 – May 24 |
| Aberdeen | 4a | May 8 | September 29 | May 15 – May 29 |
| Brookings | 4b | May 6 | October 1 | May 13 – May 27 |
| Watertown | 4b | May 7 | September 30 | May 14 – May 28 |
| Mitchell | 5a | May 2 | October 6 | May 9 – May 23 |
| Yankton | 5a | April 27 | October 11 | May 4 – May 18 |
| Huron | 4b | May 6 | October 2 | May 13 – May 27 |
Acorn Squash in South Dakota: FAQ
When can I plant acorn squash in South Dakota?
Across South Dakota, the time to direct-sow acorn squash spans roughly May 3 in Sioux Falls to May 19 in Spearfish, each following that city's local frost dates.
Does the acorn squash planting date vary across South Dakota?
Yes. South Dakota publishes 13 cities with their own frost dates, so the right acorn squash 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 acorn squash take to grow in South Dakota?
Acorn Squash takes about 80–100 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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