Frost Dates for Phoenix, AZ
In Phoenix, AZ, the average last spring frost is around Jan 8 and the average first fall frost around Dec 25, for a growing season of about 354 days. For frost-tender plants, wait until Feb 12, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Phoenix Deer Valley Muni Airport, AZ weather station, 8 miles away, elevation 1,455 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% | Feb 12 | Dec 5 |
| 20% | Feb 1 | Dec 11 |
| 30% | Jan 23 | Dec 15 |
| 40% | Jan 14 | Dec 20 |
| 50% | Jan 8 | Dec 25 |
| 60% | Jan 2 | Dec 29 |
| 70% | Dec 31 | Jan 2 |
| 80% | Dec 24 | Jan 9 |
| 90% | Dec 16 | Jan 23 |
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) | Feb 1 | Dec 11 |
| Frost / freeze (32°F) | Jan 8 | Dec 25 |
| Hard freeze (28°F) | Jan 8 | Jan 7 |
Planting calendar for Phoenix
Transplant Jan 15 – Jan 29
Transplant Jan 22 – Feb 5
Transplant Jan 22 – Feb 5
Transplant Jan 15 – Jan 29
Sow or transplant Jan 15 – Jan 29
Sow or transplant Jan 15 – Jan 29
Sow or transplant Jan 22 – Feb 5
Sow or transplant Dec 11 – Dec 25
Fall sowing Oct 30 – Nov 27
Fall sowing Oct 30 – Nov 20
Fall sowing Oct 16 – Oct 30
Sow or transplant Dec 11 – Dec 25
Fall sowing Oct 16 – Nov 13
Transplant Dec 25 – Jan 8
Fall sowing Oct 2 – Oct 16
Transplant Dec 18 – Jan 1
Fall sowing Oct 2 – Oct 16
Fall sowing Oct 2 – Oct 16
Fall sowing Nov 13 – Dec 4
Fall sowing Oct 16 – Oct 30
Plant Dec 11 – Dec 25
Based on the average last frost (Jan 8) and first frost (Dec 25). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.