Frost Dates for San Diego, CA
In San Diego, CA, the average last spring frost is around Jan 6 and the average first fall frost around Dec 21, for a growing season of about 350 days. For frost-tender plants, wait until Feb 7, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the El Cajon, CA weather station, 12 miles away, elevation 495 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 7 | Dec 1 |
| 20% | Jan 30 | Dec 7 |
| 30% | Jan 21 | Dec 12 |
| 40% | Jan 12 | Dec 17 |
| 50% | Jan 6 | Dec 21 |
| 60% | Dec 31 | Dec 25 |
| 70% | Dec 28 | Dec 30 |
| 80% | Dec 22 | Jan 4 |
| 90% | Dec 13 | Jan 15 |
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 6 | Dec 6 |
| Frost / freeze (32°F) | Jan 6 | Dec 21 |
| Hard freeze (28°F) | Dec 31 | Dec 30 |
Planting calendar for San Diego
Transplant Jan 13 – Jan 27
Transplant Jan 20 – Feb 3
Transplant Jan 20 – Feb 3
Transplant Jan 13 – Jan 27
Sow or transplant Jan 13 – Jan 27
Sow or transplant Jan 13 – Jan 27
Sow or transplant Jan 20 – Feb 3
Sow or transplant Dec 9 – Dec 23
Fall sowing Oct 26 – Nov 23
Fall sowing Oct 26 – Nov 16
Fall sowing Oct 12 – Oct 26
Sow or transplant Dec 9 – Dec 23
Fall sowing Oct 12 – Nov 9
Transplant Dec 23 – Jan 6
Fall sowing Sep 28 – Oct 12
Transplant Dec 16 – Dec 30
Fall sowing Sep 28 – Oct 12
Fall sowing Sep 28 – Oct 12
Fall sowing Nov 9 – Nov 30
Fall sowing Oct 12 – Oct 26
Plant Dec 9 – Dec 23
Based on the average last frost (Jan 6) and first frost (Dec 21). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.