Byron, CA frost dates
Frost is light and occasional here — typically a few cold nights around midwinter (about 10 a year). Cover tender plants when frost is forecast.
How Byron compares
- In a typical year, frost nights in Byron fall between December 10 and January 19. In 1 year in 10 the first frost comes as early as November 26, or the last frost as late as February 17.
- Compared with Brentwood, CA, 13 km away, the last frost here is 7 days later than there.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 25 |
| 50% (median) | January 19 |
| 10% (safe for tender plants) | February 17 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 26 |
| 50% (median) | December 10 |
| 90% (late) | January 7 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Gardening where frost is rare
Byron, CA only freezes on a few winter nights, so the usual "plant after the last frost" rule doesn't apply. Heat and rainfall decide the seasons instead:
- Cool-season crops (lettuce, broccoli, peas, carrots) grow best from fall through late winter.
- Warm-season crops (tomatoes, peppers, beans, squash) do best planted in late winter to spring, and again in late summer for a fall crop — midsummer heat can stop tomatoes setting fruit.
- Heat lovers (okra, sweet potatoes, melons) can be planted through spring and early summer.
About these dates
Based on 1991–2020 NOAA climate normals for the Tracy Pumping Plt, CA weather station, 5 km away (elevation 62 ft (19 m)).
Frost dates near Byron
- Discovery Bay Jan 19 · Dec 10
- Brentwood Jan 12 · Dec 19
- Knightsen Jan 12 · Dec 19
- Livermore Feb 15 · Dec 2
- Tracy Feb 25 · Nov 26
- Oakley Jan 12 · Dec 19
- Holt Feb 5 · Dec 8
- Bethel Island Jan 12 · Dec 19
- Antioch Jan 12 · Dec 19
- Clayton Mar 8 · Dec 22
Frequently asked questions
When is the last frost in Byron, CA?
The median last spring frost in Byron, CA is January 19. There is still about a 10% chance of frost after February 17, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Byron, CA?
The median first fall frost is December 10, with about a 10% chance of frost before November 26.
How long is the growing season in Byron, CA?
About 325 days between the median last spring frost and first fall frost.
What planting zone is Byron, CA?
Byron, CA is in USDA hardiness zone 9b.