Growing in Denver
- USDA zone (2023)
- 5b-6a
- Median last frost
- May 5
- Median first frost
- October 5
- Growing season
- ~153 days
Frost dates are medians from NOAA climate normals: in half of years, frost comes later. The windows below are computed from each crop's planting rules against this city's dates, treat them as the center of the target, not the edges.
Tomato in Denver
| Step | Window | Notes |
|---|---|---|
| Start seed indoors | March 10 to March 24 | Start seed indoors 6-8 weeks before the median last spring frost. |
| Transplant out | May 12 to June 2 | soil ≥ 60°F. Set transplants out 1-4 weeks after the last-frost date, once soil holds 60°F. |
→ Full tomato calendar & suitable varieties for Denver
Pepper in Denver
| Step | Window | Notes |
|---|---|---|
| Start seed indoors | February 24 to March 10 | Peppers germinate slowly and need 8-10 weeks indoors, longer than tomatoes. |
| Transplant out | May 19 to June 2 | soil ≥ 65°F. Peppers sulk in cold soil; waiting a week past the tomato date usually pays. |
→ Full pepper calendar & suitable varieties for Denver
Other crops with rules for this climate
Data sources
Evidence: 2 sources, all independent references.
- USDA Plant Hardiness Zone Map (2023) · USDA Agricultural Research Service / Oregon State PRISM (2023), University or Government
- U.S. Climate Normals (1991-2020) · NOAA National Centers for Environmental Information (2021), University or Government