When to plant scallion (green onion) in Wyoming
Wyoming spans USDA zones 4a–5b, so the right time to plant scallion (green onion) shifts by weeks across the state. The window to sow seed directly outdoors runs from about April 12 in Casper to May 23 in Jackson — below are local dates for 11 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Cheyenne | 5b | May 14 | October 1 | April 16 – May 28 |
| Casper | 5a | May 10 | September 29 | April 12 – May 24 |
| Gillette | 4b | May 15 | October 1 | April 17 – May 29 |
| Laramie | 4a | June 7 | September 4 | May 10 – June 21 |
| Rock Springs | 5a | May 24 | September 24 | April 26 – June 7 |
| Sheridan | 5a | May 21 | September 23 | April 23 – June 4 |
| Evanston | 5a | June 12 | September 12 | May 15 – June 26 |
| Green River | 5a | May 24 | September 22 | April 26 – June 7 |
Scallion (Green Onion) in Wyoming: FAQ
When can I plant scallion (green onion) in Wyoming?
Across Wyoming, the time to direct-sow scallion (green onion) spans roughly April 12 in Casper to May 23 in Jackson, each following that city's local frost dates.
Does the scallion (green onion) planting date vary across Wyoming?
Yes. Wyoming publishes 11 cities with their own frost dates, so the right scallion (green onion) 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 scallion (green onion) take to grow in Wyoming?
Scallion (Green Onion) takes about 60–80 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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