Last spring frost
Jun 1
Frost Dates for Durango, CO
First fall frost
Sep 27
Growing season
116 days
Hardiness zone
6b
In an average year around Durango, CO, the last spring frost (32°F) is about Jun 1 and the first fall frost is about Sep 27, giving roughly a 116-day growing season. To be safe most years, wait until May 17 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Jun 27 | Jun 13 | May 31 |
| Freeze (32°F) | Jun 15 | Jun 1 | May 17 |
| Hard (28°F) | Jun 4 | May 18 | May 1 |
| Severe (24°F) | May 20 | May 1 | Apr 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 27 | Jun 22 | Jun 19 | Jun 16 | Jun 13 | Jun 10 | Jun 8 | Jun 4 | May 31 |
| 32°F | Jun 15 | Jun 11 | Jun 7 | Jun 4 | Jun 1 | May 30 | May 26 | May 22 | May 17 |
| 28°F | Jun 4 | May 30 | May 25 | May 21 | May 18 | May 15 | May 11 | May 6 | May 1 |
| 24°F | May 20 | May 13 | May 8 | May 4 | May 1 | Apr 29 | Apr 26 | Apr 22 | Apr 16 |
| 20°F | May 2 | Apr 27 | Apr 22 | Apr 18 | Apr 15 | Apr 12 | Apr 9 | Apr 5 | Mar 31 |
| 16°F | Apr 17 | Apr 11 | Apr 7 | Apr 3 | Mar 31 | Mar 26 | Mar 20 | Mar 14 | Mar 9 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Sep 7 | Sep 19 | Sep 29 |
| Freeze (32°F) | Sep 15 | Sep 27 | Oct 9 |
| Hard (28°F) | Sep 24 | Oct 6 | Oct 20 |
| Severe (24°F) | Oct 2 | Oct 16 | Oct 31 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 7 | Sep 11 | Sep 14 | Sep 16 | Sep 19 | Sep 21 | Sep 23 | Sep 26 | Sep 29 |
| 32°F | Sep 15 | Sep 20 | Sep 22 | Sep 25 | Sep 27 | Sep 30 | Oct 2 | Oct 5 | Oct 9 |
| 28°F | Sep 24 | Sep 28 | Oct 1 | Oct 3 | Oct 6 | Oct 8 | Oct 11 | Oct 15 | Oct 20 |
| 24°F | Oct 2 | Oct 6 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 31 |
| 20°F | Oct 10 | Oct 16 | Oct 20 | Oct 23 | Oct 26 | Oct 30 | Nov 2 | Nov 6 | Nov 11 |
| 16°F | Oct 20 | Oct 26 | Oct 31 | Nov 4 | Nov 7 | Nov 11 | Nov 14 | Nov 18 | Nov 22 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Durango La Plata Co Ap, Co, about 5.4 miles away@if(!empty($station['elevation_ft'])), at 6,660 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Durango, CO?
On average, the last spring frost (32°F) around Durango, CO is about Jun 1. In cooler years it can run later, so for a safer bet many gardeners wait until May 17.
When is the first frost in the fall?
The first fall frost around Durango, CO typically arrives about Sep 27. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Jun 1 on average, or May 17 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 116 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 81303 Planting calendar → Colorado frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026