Frost dates for Gross Rsvr, 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
May 24
typical year
Safe to plant
June 10
frost is over in 9 of 10 years
First fall frost
September 23
typical year
Growing season
120 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 | – | Apr 26 – May 10 | – |
| Spinach | – | Apr 12 – May 3 | Jul 29 – Aug 12 |
| Lettuce | – | Apr 26 – May 17 | Jul 29 – Aug 12 |
| Radishes | – | Apr 26 – Jun 7 | Aug 12 – 26 |
| Onions | – | Apr 26 – May 10 | – |
| Potatoes | – | May 3 – 17 | – |
| Carrots | – | May 3 – 24 | Jul 1 – 15 |
| Beets | – | Apr 26 – May 10 | Jul 15 – 29 |
| Kale | Mar 15 – 29 | Apr 26 – May 10 | Jul 15 – 29 |
| Broccoli | Mar 15 – 29 | May 10 – 24 | Jul 15 – 29 |
| Cabbage | Mar 1 – 15 | Apr 26 – May 10 | Jul 15 – 29 |
| Garlic | – | – | Aug 12 – Sep 2 |
| Warm-season crops | |||
| Tomatoes | Apr 15 – 29 | Jun 10 – 24 | – |
| Peppers | Apr 8 – 22 | Jun 17 – Jul 1 | – |
| Cucumbers | – | Jun 10 – Jul 1 | – |
| Zucchini | – | Jun 10 – Jul 8 | – |
| Pumpkins | – | Jun 10 – Jul 1 | – |
| Green beans | – | Jun 10 – Jul 15 | – |
| Sweet corn | – | Jun 10 – Jul 8 | – |
| Basil | May 6 – 20 | Jun 17 – 24 | – |
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 10 | May 24 | May 11 |
| Fall frost before | September 9 | September 23 | October 6 |
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 10 (May 27 in a late year), and the first one in fall around October 3.
Where these dates come from
NOAA weather station GROSS RSVR, CO US (USC00053629), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 3 miles:
80025
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.