Frost dates for 81045Haswell, CO
The average last spring frost in Haswell is April 30 and the average first fall frost is October 13, giving a typical growing season of about 165 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 30
- Average first fall frost
- Oct 13
- Growing season
- 165 days
Safer after May 12 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 185 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) | Apr 28 · May 9 · May 23 | Sep 24 · Oct 5 · Oct 15 | 147 days | 100% |
| Frost / freeze (32°F) | Apr 15 · Apr 30 · May 12 | Oct 1 · Oct 13 · Oct 24 | 165 days | 100% |
| Hard freeze (28°F) | Apr 5 · Apr 19 · May 2 | Oct 8 · Oct 21 · Nov 1 | 183 days | 100% |
Planting calendar for Haswell
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 | Mar 30 – Jun 5 |
| Tomatoes | Transplant outdoors | May 16 – Jun 23 |
| Peppers | Start seeds indoors | Mar 30 – Apr 30 |
| Peppers | Transplant outdoors | May 30 – Jun 30 |
| Eggplant | Start seeds indoors | Apr 16 – May 15 |
| Eggplant | Transplant outdoors | May 30 – Jun 30 |
| Cucumbers | Sow outdoors | May 30 – Jul 3 |
| Summer squash | Sow outdoors | May 16 – Jun 30 |
| Winter squash & pumpkins | Sow outdoors | May 30 – Jun 30 |
| Snap beans | Sow outdoors | May 16 – Jul 26 |
| Sweet corn | Sow outdoors | May 16 – Jun 23 |
| Watermelon & cantaloupe | Sow outdoors | May 30 – Jun 30 |
| Okra | Sow outdoors | May 23 – Jun 15 |
| Peas | Sow outdoors (spring) | Mar 30 – May 15 |
| Potatoes | Plant outdoors (spring) | Mar 30 – May 30 |
| Onions | Start seeds indoors (spring) | Feb 16 – Mar 15 |
| Onions | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (spring) | Mar 12 – Apr 15 |
| Broccoli | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (fall) | Jun 13 – Jun 23 |
| Broccoli | Transplant outdoors (fall) | Jul 13 – Jul 24 |
| Cabbage | Start seeds indoors (spring) | Mar 2 – Mar 30 |
| Cabbage | Transplant outdoors (spring) | Mar 30 – Apr 30 |
| Cabbage | Start seeds indoors (fall) | Jun 3 – Jul 3 |
| Cabbage | Transplant outdoors (fall) | Jul 3 – Aug 3 |
| Leaf lettuce | Sow outdoors (spring) | Mar 30 – Jun 15 |
| Leaf lettuce | Sow outdoors (fall) | Jul 3 – Aug 19 |
| Spinach | Sow outdoors (spring) | Mar 23 – May 6 |
| Spinach | Sow outdoors (fall) | Jul 20 – Aug 24 |
| Radishes | Sow outdoors (spring) | Mar 30 – May 20 |
| Radishes | Sow outdoors (fall) | Jul 3 – Sep 3 |
| Kale | Sow outdoors (spring) | Apr 16 – May 6 |
| Kale | Sow outdoors (fall) | Jun 26 – Aug 3 |
| Carrots | Sow outdoors (spring) | Apr 30 – Jun 15 |
| Carrots | Sow outdoors (fall) | Jun 3 – Jul 19 |
| Garlic | Plant outdoors (fall) | Oct 3 – Nov 3 |
Where these dates come from
ZIP code 81045 is matched to the NOAA station Eads, CO, 32.7 km away, at 4,212 ft elevation (342 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Eads, CO (used) | 4,212 ft | Apr 30 | Oct 13 |
| Las Animas, CO | 3,890 ft | Apr 29 | Oct 12 |
| Kit Carson, CO | 4,302 ft | May 10 | Oct 1 |
| John Martin Dam, CO | 3,814 ft | Apr 24 | Oct 15 |
Frost dates near Haswell
- Arlington, CO 81021 · last May 2, first Oct 8
- Wild Horse, CO 80862 · last May 4, first Oct 8
- Karval, CO 80823 · last May 9, first Oct 6
- Mc Clave, CO 81057 · last Apr 24, first Oct 15
- Kit Carson, CO 80825 · last May 10, first Oct 1
- Cheraw, CO 81030 · last Apr 30, first Oct 10
- Sugar City, CO 81076 · last May 2, first Oct 8
- Wiley, CO 81092 · last May 2, first Oct 7
Frequently asked questions
- When is the last frost in Haswell, CO?
- For ZIP code 81045, the average last spring frost (32°F) is April 30, based on NOAA 1991-2020 climate normals for the Eads, CO weather station. There is a 1-in-10 chance of a frost after May 12.
- When is the first frost in Haswell, CO?
- The average first fall frost (32°F) is October 13. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 81045?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 165 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.