Frost Dates for Newark, CA
In Newark, CA, the average last spring frost is around Jan 1 and the average first fall frost around Dec 27, for a growing season of about 365 days. For frost-tender plants, wait until Jan 22, when the chance of frost drops to 10%.
Based on NOAA 1991–2020 records from the Newark, CA weather station, under 1 mile away, elevation 10 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% | Jan 22 | Dec 9 |
| 20% | Jan 14 | Dec 15 |
| 30% | Jan 8 | Dec 19 |
| 40% | Jan 5 | Dec 23 |
| 50% | Jan 1 | Dec 27 |
| 60% | Dec 29 | Dec 29 |
| 70% | Dec 25 | Jan 2 |
| 80% | Dec 21 | Jan 7 |
| 90% | Dec 16 | Jan 14 |
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 19 | Dec 15 |
| Frost / freeze (32°F) | Jan 1 | Dec 27 |
| Hard freeze (28°F) | — | — |
Planting calendar for Newark
Transplant Jan 8 – Jan 22
Transplant Jan 15 – Jan 29
Transplant Jan 15 – Jan 29
Transplant Jan 8 – Jan 22
Sow or transplant Jan 8 – Jan 22
Sow or transplant Jan 8 – Jan 22
Sow or transplant Jan 15 – Jan 29
Sow or transplant Dec 4 – Dec 18
Fall sowing Nov 1 – Nov 29
Fall sowing Nov 1 – Nov 22
Fall sowing Oct 18 – Nov 1
Sow or transplant Dec 4 – Dec 18
Fall sowing Oct 18 – Nov 15
Transplant Dec 18 – Jan 1
Fall sowing Oct 4 – Oct 18
Transplant Dec 11 – Dec 25
Fall sowing Oct 4 – Oct 18
Fall sowing Oct 4 – Oct 18
Fall sowing Nov 15 – Dec 6
Fall sowing Oct 18 – Nov 1
Plant Dec 4 – Dec 18
Based on the average last frost (Jan 1) and first frost (Dec 27). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.