Colorado frost dates
Typical and safer frost dates for 2 cities in Colorado, each from its nearest NOAA station. Elevation matters here as much as latitude, so check the city closest to you.
| City | Last frost · typical | Last frost · safer | First frost · typical | Frost-free days |
|---|---|---|---|---|
| Denver | May 4 | May 16 | Oct 8 | 156 |
| Colorado Springs | May 3 | May 15 | Oct 8 | 158 |
Planting calendar for Denver
The largest city we cover in Colorado. Other cities: see their own page.
Frost dates
May 4
Last spring frost, typical
In half of the years that freeze, the last frost comes later.
Safer date: May 16. Only 1 freeze year in 10 has a frost after this.
Oct 8
First fall frost, typical
In half of the years that freeze, it comes earlier.
Early date: Sep 25. Only 1 freeze year in 10 freezes before this.
156
Days, typical frost-free season
From NOAA’s 1991–2020 climate normals for this station.
What to plant right now
As of Nov 9, 2026
Typical frost-free season: 156 days. Station: Denver-Stapleton, CO, 1 km away. Source: NOAA NCEI U.S. Climate Normals 1991–2020 (32°F threshold).
March
The next window opens in March.
Peppertender
Next: start indoors from Mar 7
- Start indoors
- Mar 7 – Mar 21
- Transplant outdoors
- May 16 – May 30
Parsleyhalf hardy
Next: start indoors from Mar 7
- Start indoors
- Mar 7 – Mar 21
- Sow outdoors
- May 2 – May 16
Tomatotender
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Transplant outdoors
- May 16 – May 30
Eggplanttender
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Transplant outdoors
- May 16 – May 30
Broccolihardy
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Transplant outdoors
- Apr 18 – May 16
- Sow outdoors
- Apr 18 – May 2
- Sow for fall
- Jul 3 – Jul 17
Cabbagehardy
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Transplant outdoors
- Apr 18 – May 16
- Sow outdoors
- Apr 18 – May 2
- Sow for fall
- Jul 3 – Jul 17
Cauliflowerhalf hardy
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Transplant outdoors
- May 2 – May 16
- Sow outdoors
- Apr 25 – May 16
- Sow for fall
- Jul 3 – Jul 17
Brussels sproutshardy
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Sow outdoors
- Apr 25 – Apr 25
- Sow for fall
- Jul 3 – Jul 17
Marigoldtender
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Mar 21
- Transplant outdoors
- May 16 – May 16
Calendulahalf hardy
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Sow outdoors
- May 9 – May 16
Mexican sunflowertender
Next: start indoors from Mar 21
- Start indoors
- Mar 21 – Apr 4
- Sow outdoors
- May 16 – May 16
April
The next window opens in April.
Leaf lettucehardy
Next: sow outdoors from Apr 4
- Transplant outdoors
- Apr 18 – May 2
- Sow outdoors
- Apr 4 – May 2
Head lettucehardy
Next: sow outdoors from Apr 4
- Transplant outdoors
- Apr 18 – May 2
- Sow outdoors
- Apr 4 – May 2
Zinniatender
Next: start indoors from Apr 4
- Start indoors
- Apr 4 – Apr 18
- Sow outdoors
- May 16 – May 16
Nasturtiumtender
Next: start indoors from Apr 4
- Start indoors
- Apr 4 – Apr 18
- Sow outdoors
- May 16 – May 16
Sunflowertender
Next: start indoors from Apr 4
- Start indoors
- Apr 4 – Apr 18
Cucumbertender
Next: start indoors from Apr 18
- Start indoors
- Apr 18 – May 2
- Sow outdoors
- May 16 – May 23
Summer squashtender
Next: start indoors from Apr 18
- Start indoors
- Apr 18 – May 2
- Sow outdoors
- May 16 – May 23
Winter squashtender
Next: start indoors from Apr 18
- Start indoors
- Apr 18 – May 2
- Sow outdoors
- May 23 – May 30
Watermelontender
Next: start indoors from Apr 18
- Start indoors
- Apr 18 – May 2
- Transplant outdoors
- May 23 – May 30
- Sow outdoors
- May 23 – May 30
Cantaloupetender
Next: start indoors from Apr 18
- Start indoors
- Apr 18 – Apr 25
- Sow outdoors
- May 23 – May 30
Peahardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Spinachhardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Kohlrabihardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
- Sow for fall
- Jul 3 – Jul 17
Radishhardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Beethalf hardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 16
Turniphardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Bulb onionhardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Green onionhardy
Next: sow outdoors from Apr 18
- Sow outdoors
- Apr 18 – May 2
Kalehardy
Next: sow outdoors from Apr 25
- Sow outdoors
- Apr 25 – Apr 25
- Sow for fall
- Jul 3 – Jul 17
Collardshardy
Next: sow outdoors from Apr 25
- Sow outdoors
- Apr 25 – Apr 25
- Sow for fall
- Jul 3 – Jul 17
May
The next window opens in May.
Swiss chardhalf hardy
Next: sow outdoors from May 2
- Sow outdoors
- May 2 – May 16
Carrothalf hardy
Next: sow outdoors from May 2
- Sow outdoors
- May 2 – May 16
Potatohalf hardy
Next: sow outdoors from May 2
- Sow outdoors
- May 2 – May 16
Parsniphalf hardy
Next: sow outdoors from May 2
- Sow outdoors
- May 2 – May 16
Dillhalf hardy
Next: sow outdoors from May 2
- Sow outdoors
- May 2 – May 9
Bush beantender
Next: sow outdoors from May 16
- Sow outdoors
- May 16 – May 16
Pole beantender
Next: sow outdoors from May 16
- Sow outdoors
- May 16 – May 16
Sweet corntender
Next: sow outdoors from May 16
- Sow outdoors
- May 16 – May 16
Basiltender
Next: sow outdoors from May 16
- Sow outdoors
- May 16 – May 16
Marjoramtender
Next: transplant outdoors from May 16
- Transplant outdoors
- May 16 – May 16
Pumpkintender
Next: sow outdoors from May 23
- Sow outdoors
- May 23 – May 30
Lima beantender
Next: sow outdoors from May 30
- Sow outdoors
- May 30 – May 30
August
The next window opens in August.
Sweet alyssumhardy
Next: sow for fall from Aug 14
- Sow for fall
- Aug 14 – Aug 14
No window listed
No frost-based window for these crops.
Mustard greenshalf hardy
No frost-based window listed.
No frost-based sowing window is listed for mustard greens.