Colorado · zones 5a–7a
When to plant carrots in Colorado.
Sow between Apr 1 to May 4 in a typical year, keyed to Colorado's median last frost around May 9. A second, fall sowing fits Jul 4 to Jul 30. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Carrots dates for a typical Colorado season.
Direct sow
Apr 1 to May 4
Keyed to the ~May 9 last frost. Sow 0.25" deep, 2" apart.
Fall round
Jul 4 to Jul 30
Counted back from the ~Sep 29 first frost.
Harvest
~68 days later
~0.2 lb per plant over ~2 weeks.
Colorado spans more than one climate: Zone 6 is the most common zone, but the state runs 5a to 7a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Colorado: watch for
The pests that find carrots here.
The short season here, about 143 frost-free days, keeps carrot in front of carrot rust fly only briefly. One early row cover usually carries a planting through the worst of it.
Rusty tunnels in the roots and stunted tops.
Organic fix: Cover the row; rotate away from last year's carrots.
Big green-and-black striped caterpillars on the foliage.
Organic fix: Handpick (or leave for swallowtails); Bt if heavy.
Brown spots ringed in yellow on the oldest leaves first, darkening until the tops look scorched.
Organic fix: Water at the base rather than overhead, turn under old carrot tops, and leave 2 years between carrot crops.
Your season math: Colorado gives carrots about 143 frost-free days, and it needs roughly 68 days to a first harvest. That fits about 4 re-sown rounds across the season, so you can keep it coming instead of picking once.
Planting carrots in Colorado: questions
When should I plant carrots in Colorado?+
In a typical Colorado year, sow carrots between Apr 1 to May 4, keyed to the state's median last frost around May 9. There's also a fall window: Jul 4 to Jul 30. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Colorado?+
Colorado spans zones 5a–7a, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many carrots plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.