When to plant watercress in Colorado
Colorado spans USDA zones 5b–7a, so the right time to plant watercress shifts by weeks across the state. The window to sow seed directly outdoors runs from about March 31 in Grand Junction to June 7 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 | April 20 – May 18 |
| Colorado Springs | 6a | May 3 | October 8 | April 19 – May 17 |
| Aurora | 6a | May 7 | October 8 | April 23 – May 21 |
| Fort Collins | 5b | May 2 | October 7 | April 18 – May 16 |
| Lakewood | 6a | May 3 | October 7 | April 19 – May 17 |
| Thornton | 6a | May 2 | October 11 | April 18 – May 16 |
| Arvada | 6a | May 5 | October 5 | April 21 – May 19 |
| Westminster | 6a | May 2 | October 11 | April 18 – May 16 |
Watercress in Colorado: FAQ
When can I plant watercress in Colorado?
Across Colorado, the time to direct-sow watercress spans roughly March 31 in Grand Junction to June 7 in Edwards, each following that city's local frost dates.
Does the watercress planting date vary across Colorado?
Yes. Colorado publishes 70 cities with their own frost dates, so the right watercress 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 watercress take to grow in Colorado?
Watercress takes about 45–60 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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