Frost dates for 81504Grand Junction, CO
The average last spring frost in Grand Junction is April 23 and the average first fall frost is October 20, giving a typical growing season of about 179 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 23
- Average first fall frost
- Oct 20
- Growing season
- 179 days
Safer after May 9 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 178 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 21 · May 3 · May 20 | Sep 28 · Oct 10 · Oct 25 | 158 days | 100% |
| Frost / freeze (32°F) | Apr 6 · Apr 23 · May 9 | Oct 5 · Oct 20 · Nov 5 | 179 days | 100% |
| Hard freeze (28°F) | Mar 18 · Apr 8 · Apr 25 | Oct 14 · Nov 1 · Nov 15 | 207 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 23 – May 29 |
| Tomatoes | Transplant outdoors | May 9 – Jun 30 |
| Peppers | Start seeds indoors | Mar 23 – Apr 23 |
| Peppers | Transplant outdoors | May 23 – Jun 23 |
| Eggplant | Start seeds indoors | Apr 9 – May 8 |
| Eggplant | Transplant outdoors | May 23 – Jun 23 |
| Cucumbers | Sow outdoors | May 23 – Jul 10 |
| Summer squash | Sow outdoors | May 9 – Jun 23 |
| Winter squash & pumpkins | Sow outdoors | May 23 – Jun 23 |
| Snap beans | Sow outdoors | May 9 – Aug 2 |
| Sweet corn | Sow outdoors | May 9 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | May 23 – Jun 23 |
| Okra | Sow outdoors | May 16 – Jun 8 |
| Peas | Sow outdoors (spring) | Mar 23 – May 8 |
| Potatoes | Plant outdoors (spring) | Mar 23 – May 23 |
| Onions | Start seeds indoors (spring) | Feb 9 – Mar 8 |
| Onions | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (spring) | Mar 5 – Apr 8 |
| Broccoli | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Feb 23 – Mar 23 |
| Cabbage | Transplant outdoors (spring) | Mar 23 – Apr 23 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Mar 23 – Jun 8 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 16 – Apr 29 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Mar 23 – May 13 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 9 – Apr 29 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 81504 is matched to the NOAA station Grand Junction 6Ese, CO, 4.6 km away, at 4,760 ft elevation (98 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grand Junction 6Ese, CO (used) | 4,760 ft | Apr 23 | Oct 20 |
| Grand Junction Wfo, CO | 4,826 ft | Apr 14 | Oct 23 |
| Grand Junction Walker Fld, CO | 4,858 ft | Apr 28 | Oct 16 |
| Palisade, CO | 4,751 ft | Apr 17 | Oct 26 |
Frost dates near Grand Junction
- Clifton, CO 81520 · last Apr 23, first Oct 20
- Grand Junction, CO 81501 · last Apr 23, first Oct 20
- Palisade, CO 81526 · last Apr 17, first Oct 26
- Whitewater, CO 81527 · last Apr 23, first Oct 20
- Fruita, CO 81521 · last Apr 27, first Oct 11
- Glade Park, CO 81523 · last May 21, first Sep 26
- Loma, CO 81524 · last Apr 27, first Oct 11
- De Beque, CO 81630 · last Apr 17, first Oct 26
Frequently asked questions
- When is the last frost in Grand Junction, CO?
- For ZIP code 81504, the average last spring frost (32°F) is April 23, based on NOAA 1991-2020 climate normals for the Grand Junction 6Ese, CO weather station. There is a 1-in-10 chance of a frost after May 9.
- When is the first frost in Grand Junction, CO?
- The average first fall frost (32°F) is October 20. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 81504?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 179 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.