Frost dates for 80728Fleming, CO
The average last spring frost in Fleming is May 4 and the average first fall frost is October 11, giving a typical growing season of about 157 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 4
- Average first fall frost
- Oct 11
- Growing season
- 157 days
Safer after May 16 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 189 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 1 · May 13 · May 27 | Sep 20 · Oct 1 · Oct 12 | 140 days | 100% |
| Frost / freeze (32°F) | Apr 21 · May 4 · May 16 | Sep 29 · Oct 11 · Oct 20 | 157 days | 100% |
| Hard freeze (28°F) | Apr 12 · Apr 25 · May 8 | Oct 6 · Oct 19 · Oct 28 | 175 days | 100% |
Planting calendar for Fleming
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 3 – Jun 9 |
| Tomatoes | Transplant outdoors | May 20 – Jun 21 |
| Peppers | Start seeds indoors | Apr 3 – May 4 |
| Peppers | Transplant outdoors | Jun 3 – Jul 4 |
| Eggplant | Start seeds indoors | Apr 20 – May 19 |
| Eggplant | Transplant outdoors | Jun 3 – Jul 4 |
| Cucumbers | Sow outdoors | Jun 3 – Jul 1 |
| Summer squash | Sow outdoors | May 20 – Jul 4 |
| Winter squash & pumpkins | Sow outdoors | Jun 3 – Jul 4 |
| Snap beans | Sow outdoors | May 20 – Jul 24 |
| Sweet corn | Sow outdoors | May 20 – Jun 21 |
| Watermelon & cantaloupe | Sow outdoors | Jun 3 – Jul 4 |
| Okra | Sow outdoors | May 27 – Jun 19 |
| Peas | Sow outdoors (spring) | Apr 3 – May 19 |
| Potatoes | Plant outdoors (spring) | Apr 3 – Jun 3 |
| Onions | Start seeds indoors (spring) | Feb 20 – Mar 19 |
| Onions | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (spring) | Mar 16 – Apr 19 |
| Broccoli | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (fall) | Jun 11 – Jun 21 |
| Broccoli | Transplant outdoors (fall) | Jul 11 – Jul 22 |
| Cabbage | Start seeds indoors (spring) | Mar 6 – Apr 3 |
| Cabbage | Transplant outdoors (spring) | Apr 3 – May 4 |
| Cabbage | Start seeds indoors (fall) | Jun 1 – Jul 1 |
| Cabbage | Transplant outdoors (fall) | Jul 1 – Aug 1 |
| Leaf lettuce | Sow outdoors (spring) | Apr 3 – Jun 19 |
| Leaf lettuce | Sow outdoors (fall) | Jul 1 – Aug 17 |
| Spinach | Sow outdoors (spring) | Mar 27 – May 10 |
| Spinach | Sow outdoors (fall) | Jul 18 – Aug 22 |
| Radishes | Sow outdoors (spring) | Apr 3 – May 24 |
| Radishes | Sow outdoors (fall) | Jul 1 – Sep 1 |
| Kale | Sow outdoors (spring) | Apr 20 – May 10 |
| Kale | Sow outdoors (fall) | Jun 24 – Aug 1 |
| Carrots | Sow outdoors (spring) | May 4 – Jun 19 |
| Carrots | Sow outdoors (fall) | Jun 1 – Jul 17 |
| Garlic | Plant outdoors (fall) | Oct 1 – Nov 1 |
Where these dates come from
ZIP code 80728 is matched to the NOAA station Fleming 3Sw, CO, 1.5 km away, at 4,256 ft elevation (9 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Fleming 3Sw, CO (used) | 4,256 ft | May 4 | Oct 11 |
| Leroy 5 Wsw, CO | 4,467 ft | May 10 | Oct 6 |
| Crook, CO | 3,709 ft | May 11 | Oct 4 |
| Sterling, CO | 3,974 ft | Apr 30 | Oct 9 |
Frost dates near Fleming
- Haxtun, CO 80731 · last May 6, first Oct 7
- Iliff, CO 80736 · last Apr 30, first Oct 9
- Crook, CO 80726 · last May 11, first Oct 4
- Sterling, CO 80751 · last Apr 30, first Oct 9
- Paoli, CO 80746 · last May 11, first Oct 3
- Atwood, CO 80722 · last Apr 30, first Oct 9
- Peetz, CO 80747 · last May 15, first Sep 30
- Sedgwick, CO 80749 · last May 6, first Oct 7
Frequently asked questions
- When is the last frost in Fleming, CO?
- For ZIP code 80728, the average last spring frost (32°F) is May 4, based on NOAA 1991-2020 climate normals for the Fleming 3Sw, CO weather station. There is a 1-in-10 chance of a frost after May 16.
- When is the first frost in Fleming, CO?
- The average first fall frost (32°F) is October 11. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 80728?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 157 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.