Frost dates for Allenspark, CO
When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.
Last spring frost
June 14
typical year
Safe to plant
June 28
frost is over in 9 of 10 years
First fall frost
September 12
typical year
Growing season
92 days
frost-free, typical year
Frost watch this week
Tonight's and the next six nights' lows from the National Weather Service forecast for the station's location. Frost: 32°F or colder. Possible frost: 33–36°F, mostly in low spots on clear, still nights.
When to plant
Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.
| Crop | Start indoors | Plant outside | Fall planting |
|---|---|---|---|
| Cool-season crops | |||
| Peas | – | May 17 – 31 | – |
| Spinach | – | May 3 – 24 | Jul 18 – Aug 1 |
| Lettuce | – | May 17 – Jun 7 | Jul 18 – Aug 1 |
| Radishes | – | May 17 – Jun 28 | Aug 1 – 15 |
| Onions | – | May 17 – 31 | – |
| Potatoes | Season usually too short. Try a quick variety or row covers. | ||
| Carrots | – | May 24 – Jun 14 | Jun 20 – Jul 4 |
| Beets | – | May 17 – 31 | Jul 4 – 18 |
| Kale | Apr 5 – 19 | May 17 – 31 | Jul 4 – 18 |
| Broccoli | Apr 5 – 19 | May 31 – Jun 14 | Jul 4 – 18 |
| Cabbage | Mar 22 – Apr 5 | May 17 – 31 | Jul 4 – 18 |
| Garlic | – | – | Aug 1 – 22 |
| Warm-season crops | |||
| Tomatoes | May 3 – 17 | Jun 28 – Jul 12 | – |
| Peppers | Season usually too short. Try a quick variety or row covers. | ||
| Cucumbers | – | Jun 28 – Jul 19 | – |
| Zucchini | – | Jun 28 – Jul 26 | – |
| Pumpkins | Season usually too short. Try a quick variety or row covers. | ||
| Green beans | – | Jun 28 – Jul 4 | – |
| Sweet corn | Season usually too short. Try a quick variety or row covers. | ||
| Basil | May 24 – Jun 7 | Jul 5 – 12 | – |
Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.
The year at a glance
Start indoors Plant outside Fall planting
The chance of frost, by date
| 1 year in 10 | Half of years | 9 years in 10 | |
|---|---|---|---|
| Spring frost after | June 28 | June 14 | May 24 |
| Fall frost before | August 25 | September 12 | September 25 |
Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.
Hard freeze (28°F)
A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around May 27 (June 15 in a late year), and the first one in fall around September 25.
Where these dates come from
NOAA weather station ALLENSPARK 3NW, CO US (USC00050185), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 6 miles:
80510, 80540
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.