When to plant catnip in Colorado
Colorado spans USDA zones 5b–7a, so the right time to plant catnip shifts by weeks across the state. The window to transplant seedlings outdoors runs from about April 14 in Grand Junction to June 21 in Edwards — below are local dates for 70 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Transplant out |
|---|---|---|---|---|
| Denver | 6a | May 4 | October 8 | May 4 – May 18 |
| Colorado Springs | 6a | May 3 | October 8 | May 3 – May 17 |
| Aurora | 6a | May 7 | October 8 | May 7 – May 21 |
| Fort Collins | 5b | May 2 | October 7 | May 2 – May 16 |
| Lakewood | 6a | May 3 | October 7 | May 3 – May 17 |
| Thornton | 6a | May 2 | October 11 | May 2 – May 16 |
| Arvada | 6a | May 5 | October 5 | May 5 – May 19 |
| Westminster | 6a | May 2 | October 11 | May 2 – May 16 |
Catnip in Colorado: FAQ
When can I plant catnip in Colorado?
Across Colorado, the time to transplant catnip spans roughly April 14 in Grand Junction to June 21 in Edwards, each following that city's local frost dates.
Does the catnip planting date vary across Colorado?
Yes. Colorado publishes 70 cities with their own frost dates, so the right catnip planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
Never miss a window in your area
An email when it’s time to start seeds, transplant, and sow — timed to your frost dates. Double opt-in, one-click unsubscribe, no spam.