Frost Dates for Grand Junction, CO
In Grand Junction, CO, the average last spring frost is around Apr 14 and the average first fall frost around Oct 23, for a growing season of about 190 days. For frost-tender plants, wait until Apr 28, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Grand Junction Wfo, CO weather station, 3 miles away, elevation 4,826 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.
Frost probability by date
Chance of a 32°F frost after the spring date, or before the fall date.
| Chance | Last spring frost | First fall frost |
|---|---|---|
| 10% | Apr 28 | Oct 11 |
| 20% | Apr 22 | Oct 15 |
| 30% | Apr 20 | Oct 18 |
| 40% | Apr 17 | Oct 21 |
| 50% | Apr 14 | Oct 23 |
| 60% | Apr 11 | Oct 26 |
| 70% | Apr 8 | Oct 29 |
| 80% | Apr 5 | Nov 1 |
| 90% | Apr 1 | Nov 6 |
Light frost vs. hard freeze
Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.
| Temperature | Last in spring | First in fall |
|---|---|---|
| Light frost (36°F) | Apr 25 | Oct 14 |
| Frost / freeze (32°F) | Apr 14 | Oct 23 |
| Hard freeze (28°F) | Apr 2 | Nov 2 |
Planting calendar for Grand Junction
Transplant Apr 21 – May 5
Transplant Apr 28 – May 12
Transplant Apr 28 – May 12
Transplant Apr 21 – May 5
Sow or transplant Apr 21 – May 5
Sow or transplant Apr 21 – May 5
Sow or transplant Apr 28 – May 12
Sow or transplant Mar 17 – Mar 31
Fall sowing Aug 28 – Sep 25
Fall sowing Aug 28 – Sep 18
Fall sowing Aug 14 – Aug 28
Sow or transplant Mar 17 – Mar 31
Fall sowing Aug 14 – Sep 11
Transplant Mar 31 – Apr 14
Fall sowing Jul 31 – Aug 14
Transplant Mar 24 – Apr 7
Fall sowing Jul 31 – Aug 14
Fall sowing Jul 31 – Aug 14
Fall sowing Sep 11 – Oct 2
Fall sowing Aug 14 – Aug 28
Plant Mar 17 – Mar 31
Based on the average last frost (Apr 14) and first frost (Oct 23). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.