When to plant garlic in Colorado
Colorado spans USDA zones 5b–7a, so the right time to plant garlic shifts by weeks across the state. The window to plant for fall/overwintering runs from about August 10 in Edwards to September 25 in Grand Junction — below are local dates for 70 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Fall-plant |
|---|---|---|---|---|
| Denver | 6a | May 4 | October 8 | September 10 – September 24 |
| Colorado Springs | 6a | May 3 | October 8 | September 10 – September 24 |
| Aurora | 6a | May 7 | October 8 | September 10 – September 24 |
| Fort Collins | 5b | May 2 | October 7 | September 9 – September 23 |
| Lakewood | 6a | May 3 | October 7 | September 9 – September 23 |
| Thornton | 6a | May 2 | October 11 | September 13 – September 27 |
| Arvada | 6a | May 5 | October 5 | September 7 – September 21 |
| Westminster | 6a | May 2 | October 11 | September 13 – September 27 |
Garlic in Colorado: FAQ
When can I plant garlic in Colorado?
Across Colorado, the time to fall-plant garlic spans roughly August 10 in Edwards to September 25 in Grand Junction, each following that city's local frost dates.
Does the garlic planting date vary across Colorado?
Yes. Colorado publishes 70 cities with their own frost dates, so the right garlic planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
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