When to plant in Commerce City, CO
USDA Zone 6aCommerce City, Colorado frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 6a means Commerce City sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
BRIGHTON 3 SE · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Commerce City’s own odds, recorded at BRIGHTON 3 SE.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 27 | May 13 | May 3 | Sep 17 | Sep 30 | Oct 10 |
| 32°F | May 16 | May 3 | Apr 22 | Sep 26 | Oct 7 | Oct 19 |
| 28°F | May 7 | Apr 23 | Apr 8 | Oct 4 | Oct 16 | Oct 29 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Commerce City, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 15 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Commerce City planting FAQ
When is the last spring frost in Commerce City, CO?
Plan for the last spring frost in Commerce City around May 3 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Commerce City, CO?
The first fall frost in Commerce City typically arrives around October 7 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Commerce City in?
Commerce City is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Commerce City?
There are roughly 157 frost-free days in Commerce City (a moderate growing season), running from the average last frost around May 3 to the first fall frost near October 7.
When should I plant tomatoes in Commerce City?
In Commerce City, start tomato seeds indoors around March 8–March 22, then transplant seedlings outdoors around May 10 once the danger of frost has passed.
Never miss a window in Commerce City
An email when it’s time to start seeds, transplant, and sow — timed to Commerce City’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Brighton · 9 km
- Thornton · 13 km
- Welby · 15 km
- Denver · 15 km
- Northglenn · 16 km
- Sherrelwood · 18 km
- Federal Heights · 19 km
- Aurora · 20 km
Frost dates recorded at BRIGHTON 3 SE, 8 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Commerce City, CO — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00050950. Retrieved from https://blissgarden.com/colorado/commerce-city.