Frost Dates for Poway, CA
In Poway, CA, the average last spring frost is around Jan 5 and the average first fall frost around Jan 2, for a growing season of about 365 days. For frost-tender plants, wait until Feb 1, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Rancho Bernardo, CA weather station, 4 miles away, elevation 690 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 1 | Dec 13 |
| 20% | Jan 23 | Dec 21 |
| 30% | Jan 15 | Dec 28 |
| 40% | Jan 10 | Dec 31 |
| 50% | Jan 5 | Jan 2 |
| 60% | Jan 1 | Jan 5 |
| 70% | Dec 29 | Jan 11 |
| 80% | Dec 24 | Jan 18 |
| 90% | Dec 13 | Jan 31 |
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) | Jan 23 | Dec 23 |
| Frost / freeze (32°F) | Jan 5 | Jan 2 |
| Hard freeze (28°F) | — | — |
Planting calendar for Poway
Transplant Jan 12 – Jan 26
Transplant Jan 19 – Feb 2
Transplant Jan 19 – Feb 2
Transplant Jan 12 – Jan 26
Sow or transplant Jan 12 – Jan 26
Sow or transplant Jan 12 – Jan 26
Sow or transplant Jan 19 – Feb 2
Sow or transplant Dec 8 – Dec 22
Fall sowing Nov 7 – Dec 5
Fall sowing Nov 7 – Nov 28
Fall sowing Oct 24 – Nov 7
Sow or transplant Dec 8 – Dec 22
Fall sowing Oct 24 – Nov 21
Transplant Dec 22 – Jan 5
Fall sowing Oct 10 – Oct 24
Transplant Dec 15 – Dec 29
Fall sowing Oct 10 – Oct 24
Fall sowing Oct 10 – Oct 24
Fall sowing Nov 21 – Dec 12
Fall sowing Oct 24 – Nov 7
Plant Dec 8 – Dec 22
Based on the average last frost (Jan 5) and first frost (Jan 2). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.