Last frost date in Brentwood, CA
Expect the last frost in Brentwood around January 12. Frost after February 1 happens in only one year out of ten. The first fall frost usually arrives about December 19, which leaves 343 frost-free days. An early freeze before November 29 happens one year in ten.
- Safe after (10% risk)
- Feb 1
- Average first frost
- Dec 19
- Frost-free season
- 343 days
- Hard freeze (28°F) ends
- Jan 2
No frost in the next 6 nights
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2254°
- FriOct 2350°
- SatOct 2452°
- SunOct 2553°
- MonOct 2652°
- TueOct 2752°
Planting calendar for Brentwood
Windows count forward or back from the average frost dates above. Click a crop for dates across California.
TomatoesFeb 15–Mar 1
PumpkinsFeb 15–Mar 1
SunflowersFeb 15–Mar 8
CucumbersFeb 22–Mar 1
CornFeb 15–Mar 1
Sweet potatoesFeb 15–Mar 1
WatermelonFeb 15–Mar 1
Green beansFeb 15–Mar 8
ZucchiniFeb 15–Mar 1
OkraFeb 15–Mar 1
PeppersFeb 15–Mar 1
BasilFeb 15–Mar 1
Butternut squashFeb 15–Mar 1
CantaloupeFeb 15–Mar 1
EggplantFeb 15–Mar 1
PotatoesDec 15–Dec 29
OnionsDec 1–Dec 22
CarrotsDec 22–Jan 26
LettuceDec 29–Jan 19
BroccoliDec 15–Dec 29
BeetsDec 15–Jan 26
PeasDec 1–Dec 15
CabbageDec 15–Dec 29
RadishesDec 8–Jan 19
Brussels sproutsDec 29–Jan 12
SpinachDec 1–Dec 22
CilantroDec 29–Jan 19
KaleDec 15–Dec 29
Collard greensDec 15–Dec 29
TurnipsDec 15–Dec 29
DillJan 12–Jan 26
CeleryJan 19–Jan 26
CauliflowerDec 29–Jan 12
LeeksDec 29–Jan 12
Swiss chardDec 29–Jan 26
ParsleyDec 29–Jan 19
Tulip bulbsDec 15–Jan 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
StrawberriesDec 15–Dec 29
AsparagusDec 15–Dec 29Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Dec 20 | Jan 12 | Feb 1 | Nov 29 | Dec 19 | Jan 12 |
| Hard freeze, 28°F | Dec 16 | Jan 2 | Jan 22 | Dec 9 | Dec 29 | Jan 16 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Antioch Pumping Plt #3 (USC00040232) sits 3.8 miles from the center of Brentwood at 60 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Brentwood, CA?
The average last frost date in Brentwood is January 12, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after February 1.
When is the first frost in Brentwood?
The first frost in fall usually comes around December 19. One year in ten it arrives before November 29.
How long is the growing season in Brentwood?
About 343 days between the average last and first frost.
When should I plant tomatoes in Brentwood?
Plant tomato seedlings outside from February 15 to March 1. Start seeds indoors six to eight weeks earlier.
Nearby in California
- OakleyJan 12
- AntiochJan 12
- PittsburgJan 12
- Mountain HouseJan 19
- Bay PointJan 9
- ConcordJan 9
- DanvilleMar 8
- San RamonMar 8
- LivermoreFeb 15
- Walnut CreekJan 7
- DublinFeb 15
- Pleasant HillJan 7