Frost dates for 81505Grand Junction, CO
The average last spring frost in Grand Junction is April 28 and the average first fall frost is October 16, giving a typical growing season of about 171 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 28
- Average first fall frost
- Oct 16
- Growing season
- 171 days
Safer after May 14 (1-in-10 risk)
Possible by Oct 3 (1-in-10 risk)
Last frost typically in 176 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 25 · May 8 · May 25 | Sep 24 · Oct 6 · Oct 19 | 152 days | 100% |
| Frost / freeze (32°F) | Apr 11 · Apr 28 · May 14 | Oct 3 · Oct 16 · Oct 29 | 171 days | 100% |
| Hard freeze (28°F) | Mar 24 · Apr 13 · May 2 | Oct 12 · Oct 27 · Nov 10 | 196 days | 100% |
Planting calendar for Grand Junction
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 28 – Jun 3 |
| Tomatoes | Transplant outdoors | May 14 – Jun 26 |
| Peppers | Start seeds indoors | Mar 28 – Apr 28 |
| Peppers | Transplant outdoors | May 28 – Jun 28 |
| Eggplant | Start seeds indoors | Apr 14 – May 13 |
| Eggplant | Transplant outdoors | May 28 – Jun 28 |
| Cucumbers | Sow outdoors | May 28 – Jul 6 |
| Summer squash | Sow outdoors | May 14 – Jun 28 |
| Winter squash & pumpkins | Sow outdoors | May 28 – Jun 28 |
| Snap beans | Sow outdoors | May 14 – Jul 29 |
| Sweet corn | Sow outdoors | May 14 – Jun 26 |
| Watermelon & cantaloupe | Sow outdoors | May 28 – Jun 28 |
| Okra | Sow outdoors | May 21 – Jun 13 |
| Peas | Sow outdoors (spring) | Mar 28 – May 13 |
| Potatoes | Plant outdoors (spring) | Mar 28 – May 28 |
| Onions | Start seeds indoors (spring) | Feb 14 – Mar 13 |
| Onions | Transplant outdoors (spring) | Apr 14 – May 13 |
| Broccoli | Start seeds indoors (spring) | Mar 10 – Apr 13 |
| Broccoli | Transplant outdoors (spring) | Apr 14 – May 13 |
| Broccoli | Start seeds indoors (fall) | Jun 16 – Jun 26 |
| Broccoli | Transplant outdoors (fall) | Jul 16 – Jul 27 |
| Cabbage | Start seeds indoors (spring) | Feb 28 – Mar 28 |
| Cabbage | Transplant outdoors (spring) | Mar 28 – Apr 28 |
| Cabbage | Start seeds indoors (fall) | Jun 6 – Jul 6 |
| Cabbage | Transplant outdoors (fall) | Jul 6 – Aug 6 |
| Leaf lettuce | Sow outdoors (spring) | Mar 28 – Jun 13 |
| Leaf lettuce | Sow outdoors (fall) | Jul 6 – Aug 22 |
| Spinach | Sow outdoors (spring) | Mar 21 – May 4 |
| Spinach | Sow outdoors (fall) | Jul 23 – Aug 27 |
| Radishes | Sow outdoors (spring) | Mar 28 – May 18 |
| Radishes | Sow outdoors (fall) | Jul 6 – Sep 6 |
| Kale | Sow outdoors (spring) | Apr 14 – May 4 |
| Kale | Sow outdoors (fall) | Jun 29 – Aug 6 |
| Carrots | Sow outdoors (spring) | Apr 28 – Jun 13 |
| Carrots | Sow outdoors (fall) | Jun 6 – Jul 22 |
| Garlic | Plant outdoors (fall) | Oct 6 – Nov 6 |
Where these dates come from
ZIP code 81505 is matched to the NOAA station Grand Junction Walker Fld, CO, 5.8 km away, at 4,858 ft elevation (278 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grand Junction Walker Fld, CO (used) | 4,858 ft | Apr 28 | Oct 16 |
| Grand Junction Wfo, CO | 4,826 ft | Apr 14 | Oct 23 |
| Colorado Nm, CO | 5,781 ft | Apr 26 | Oct 16 |
| Fruita, CO | 4,498 ft | Apr 27 | Oct 11 |
Frost dates near Grand Junction
- Grand Junction, CO 81506 · last Apr 28, first Oct 16
- Fruita, CO 81521 · last Apr 27, first Oct 11
- Clifton, CO 81520 · last Apr 23, first Oct 20
- Palisade, CO 81526 · last Apr 17, first Oct 26
- Glade Park, CO 81523 · last May 21, first Sep 26
- Whitewater, CO 81527 · last Apr 23, first Oct 20
- Loma, CO 81524 · last Apr 27, first Oct 11
- Mack, CO 81525 · last Apr 27, first Oct 11
Frequently asked questions
- When is the last frost in Grand Junction, CO?
- For ZIP code 81505, the average last spring frost (32°F) is April 28, based on NOAA 1991-2020 climate normals for the Grand Junction Walker Fld, CO weather station. There is a 1-in-10 chance of a frost after May 14.
- When is the first frost in Grand Junction, CO?
- The average first fall frost (32°F) is October 16. There is a 1-in-10 chance of frost by October 3, so tender plants are at risk from that point on.
- How long is the growing season in 81505?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 171 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.