Frost Dates for Danville, CA
In Danville, CA, the average last spring frost is around Mar 8 and the average first fall frost around Dec 22, for a growing season of about 282 days. For frost-tender plants, wait until Apr 15, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Mt Diablo Junction, CA weather station, 5 miles away, elevation 2,170 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 15 | Nov 23 |
| 20% | Apr 5 | Dec 1 |
| 30% | Mar 28 | Dec 9 |
| 40% | Mar 19 | Dec 15 |
| 50% | Mar 8 | Dec 22 |
| 60% | Feb 27 | Jan 1 |
| 70% | Feb 18 | Jan 8 |
| 80% | Jan 31 | Jan 22 |
| 90% | Jan 12 | Feb 11 |
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 19 | Nov 29 |
| Frost / freeze (32°F) | Mar 8 | Dec 22 |
| Hard freeze (28°F) | Feb 8 | Jan 16 |
Planting calendar for Danville
Transplant Mar 15 – Mar 29
Transplant Mar 22 – Apr 5
Transplant Mar 22 – Apr 5
Transplant Mar 15 – Mar 29
Sow or transplant Mar 15 – Mar 29
Sow or transplant Mar 15 – Mar 29
Sow or transplant Mar 22 – Apr 5
Sow or transplant Feb 8 – Feb 22
Fall sowing Oct 27 – Nov 24
Fall sowing Oct 27 – Nov 17
Fall sowing Oct 13 – Oct 27
Sow or transplant Feb 8 – Feb 22
Fall sowing Oct 13 – Nov 10
Transplant Feb 22 – Mar 8
Fall sowing Sep 29 – Oct 13
Transplant Feb 15 – Mar 1
Fall sowing Sep 29 – Oct 13
Fall sowing Sep 29 – Oct 13
Fall sowing Nov 10 – Dec 1
Fall sowing Oct 13 – Oct 27
Plant Feb 8 – Feb 22
Based on the average last frost (Mar 8) and first frost (Dec 22). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.