Frost dates for 80737Julesburg, CO
The average last spring frost in Julesburg is May 7 and the average first fall frost is October 6, giving a typical growing season of about 152 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 7
- Average first fall frost
- Oct 6
- Growing season
- 152 days
Safer after May 18 (1-in-10 risk)
Possible by Sep 23 (1-in-10 risk)
Last frost typically in 188 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 5 · May 16 · May 29 | Sep 14 · Sep 28 · Oct 8 | 134 days | 100% |
| Frost / freeze (32°F) | Apr 23 · May 7 · May 18 | Sep 23 · Oct 6 · Oct 17 | 152 days | 100% |
| Hard freeze (28°F) | Apr 12 · Apr 27 · May 9 | Oct 2 · Oct 15 · Oct 26 | 170 days | 100% |
Planting calendar for Julesburg
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 6 – Jun 12 |
| Tomatoes | Transplant outdoors | May 23 – Jun 16 |
| Peppers | Start seeds indoors | Apr 6 – May 7 |
| Peppers | Transplant outdoors | Jun 6 – Jul 7 |
| Eggplant | Start seeds indoors | Apr 23 – May 22 |
| Eggplant | Transplant outdoors | Jun 6 – Jul 7 |
| Cucumbers | Sow outdoors | Jun 6 – Jun 26 |
| Summer squash | Sow outdoors | May 23 – Jul 7 |
| Winter squash & pumpkins | Sow outdoors | Jun 6 – Jul 7 |
| Snap beans | Sow outdoors | May 23 – Jul 19 |
| Sweet corn | Sow outdoors | May 23 – Jun 16 |
| Watermelon & cantaloupe | Sow outdoors | Jun 6 – Jul 7 |
| Okra | Sow outdoors | May 30 – Jun 22 |
| Peas | Sow outdoors (spring) | Apr 6 – May 22 |
| Potatoes | Plant outdoors (spring) | Apr 6 – Jun 6 |
| Onions | Start seeds indoors (spring) | Feb 23 – Mar 22 |
| Onions | Transplant outdoors (spring) | Apr 23 – May 22 |
| Broccoli | Start seeds indoors (spring) | Mar 19 – Apr 22 |
| Broccoli | Transplant outdoors (spring) | Apr 23 – May 22 |
| Broccoli | Start seeds indoors (fall) | Jun 6 – Jun 16 |
| Broccoli | Transplant outdoors (fall) | Jul 6 – Jul 17 |
| Cabbage | Start seeds indoors (spring) | Mar 9 – Apr 6 |
| Cabbage | Transplant outdoors (spring) | Apr 6 – May 7 |
| Cabbage | Start seeds indoors (fall) | May 27 – Jun 26 |
| Cabbage | Transplant outdoors (fall) | Jun 26 – Jul 27 |
| Leaf lettuce | Sow outdoors (spring) | Apr 6 – Jun 22 |
| Leaf lettuce | Sow outdoors (fall) | Jun 26 – Aug 12 |
| Spinach | Sow outdoors (spring) | Mar 30 – May 13 |
| Spinach | Sow outdoors (fall) | Jul 13 – Aug 17 |
| Radishes | Sow outdoors (spring) | Apr 6 – May 27 |
| Radishes | Sow outdoors (fall) | Jun 26 – Aug 27 |
| Kale | Sow outdoors (spring) | Apr 23 – May 13 |
| Kale | Sow outdoors (fall) | Jun 19 – Jul 27 |
| Carrots | Sow outdoors (spring) | May 7 – Jun 22 |
| Carrots | Sow outdoors (fall) | May 27 – Jul 12 |
| Garlic | Plant outdoors (fall) | Sep 26 – Oct 27 |
Where these dates come from
ZIP code 80737 is matched to the NOAA station Julesburg, CO, 2 km away, at 3,477 ft elevation (19 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Julesburg, CO (used) | 3,477 ft | May 7 | Oct 6 |
| Big Springs, NE | 3,379 ft | May 10 | Oct 3 |
| Chappell, NE | 3,710 ft | May 8 | Oct 5 |
| Sedgwick 5 S, CO | 3,996 ft | May 6 | Oct 7 |
Frost dates near Julesburg
- Ovid, CO 80744 · last May 7, first Oct 6
- Big Springs, NE 69122 · last May 10, first Oct 3
- Chappell, NE 69129 · last May 8, first Oct 5
- Sedgwick, CO 80749 · last May 6, first Oct 7
- Venango, NE 69168 · last May 7, first Oct 6
- Brule, NE 69127 · last May 10, first Oct 3
- Amherst, CO 80721 · last May 11, first Oct 3
- Lodgepole, NE 69149 · last May 9, first Oct 3
Frequently asked questions
- When is the last frost in Julesburg, CO?
- For ZIP code 80737, the average last spring frost (32°F) is May 7, based on NOAA 1991-2020 climate normals for the Julesburg, CO weather station. There is a 1-in-10 chance of a frost after May 18.
- When is the first frost in Julesburg, CO?
- The average first fall frost (32°F) is October 6. There is a 1-in-10 chance of frost by September 23, so tender plants are at risk from that point on.
- How long is the growing season in 80737?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 152 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.