Frost Dates for Patterson, CA
In Patterson, CA, the average last spring frost is around Jan 31 and the average first fall frost around Dec 5, for a growing season of about 312 days. For frost-tender plants, wait until Feb 25, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Modesto City Co Airport, CA weather station, 15 miles away, elevation 73 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 25 | Nov 20 |
| 20% | Feb 18 | Nov 25 |
| 30% | Feb 10 | Nov 29 |
| 40% | Feb 5 | Dec 2 |
| 50% | Jan 31 | Dec 5 |
| 60% | Jan 25 | Dec 10 |
| 70% | Jan 18 | Dec 16 |
| 80% | Jan 10 | Dec 23 |
| 90% | Dec 31 | Jan 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) | Mar 1 | Nov 22 |
| Frost / freeze (32°F) | Jan 31 | Dec 5 |
| Hard freeze (28°F) | Jan 8 | Dec 21 |
Planting calendar for Patterson
Transplant Feb 7 – Feb 21
Transplant Feb 14 – Feb 28
Transplant Feb 14 – Feb 28
Transplant Feb 7 – Feb 21
Sow or transplant Feb 7 – Feb 21
Sow or transplant Feb 7 – Feb 21
Sow or transplant Feb 14 – Feb 28
Sow or transplant Jan 3 – Jan 17
Fall sowing Oct 10 – Nov 7
Fall sowing Oct 10 – Oct 31
Fall sowing Sep 26 – Oct 10
Sow or transplant Jan 3 – Jan 17
Fall sowing Sep 26 – Oct 24
Transplant Jan 17 – Jan 31
Fall sowing Sep 12 – Sep 26
Transplant Jan 10 – Jan 24
Fall sowing Sep 12 – Sep 26
Fall sowing Sep 12 – Sep 26
Fall sowing Oct 24 – Nov 14
Fall sowing Sep 26 – Oct 10
Plant Jan 3 – Jan 17
Based on the average last frost (Jan 31) and first frost (Dec 5). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.