When to plant spinach in Colorado
Colorado spans USDA zones 5b–7a, so the right time to plant spinach shifts by weeks across the state. The window to sow seed directly outdoors runs from about March 3 in Grand Junction to May 10 in Edwards — below are local dates for 70 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Denver | 6a | May 4 | October 8 | March 23 – April 20 |
| Colorado Springs | 6a | May 3 | October 8 | March 22 – April 19 |
| Aurora | 6a | May 7 | October 8 | March 26 – April 23 |
| Fort Collins | 5b | May 2 | October 7 | March 21 – April 18 |
| Lakewood | 6a | May 3 | October 7 | March 22 – April 19 |
| Thornton | 6a | May 2 | October 11 | March 21 – April 18 |
| Arvada | 6a | May 5 | October 5 | March 24 – April 21 |
| Westminster | 6a | May 2 | October 11 | March 21 – April 18 |
Spinach in Colorado: FAQ
When can I plant spinach in Colorado?
Across Colorado, the time to direct-sow spinach spans roughly March 3 in Grand Junction to May 10 in Edwards, each following that city's local frost dates.
Does the spinach planting date vary across Colorado?
Yes. Colorado publishes 70 cities with their own frost dates, so the right spinach 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 spinach take to grow in Colorado?
Spinach takes about 40–50 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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