Last frost date in Rohnert Park, CA
In Rohnert Park, the last spring frost comes around February 25 in an average year. Wait until March 29 if you want 90% odds of no more frost. The first fall frost usually arrives about December 1, which leaves 279 frost-free days. An early freeze before November 10 happens one year in ten.
- Safe after (10% risk)
- Mar 29
- Average first frost
- Dec 1
- Frost-free season
- 279 days
- Hard freeze (28°F) ends
- Jan 20
No frost in the next 6 nights
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2244°
- FriOct 2340°
- SatOct 2441°
- SunOct 2543°
- MonOct 2643°
- TueOct 2743°
Planting calendar for Rohnert Park
Windows count forward or back from the average frost dates above. Click a crop for dates across California.
TomatoesMar 4–Mar 18
PumpkinsMar 11–Mar 25
SunflowersFeb 25–Mar 18
CucumbersMar 11–Mar 18
CornMar 4–Mar 18
Sweet potatoesMar 18–Apr 1
WatermelonMar 11–Mar 25
Green beansMar 4–Mar 25
ZucchiniMar 4–Mar 18
OkraMar 18–Apr 1
PeppersMar 11–Mar 25
BasilMar 4–Mar 18
Butternut squashMar 4–Mar 18
CantaloupeMar 11–Mar 25
EggplantMar 11–Mar 25
PotatoesJan 28–Feb 11
OnionsJan 14–Feb 4
CarrotsFeb 4–Mar 11
LettuceFeb 11–Mar 4
BroccoliJan 28–Feb 11
BeetsJan 28–Mar 11
PeasJan 14–Jan 28
CabbageJan 28–Feb 11
RadishesJan 21–Mar 4
Brussels sproutsFeb 11–Feb 25
SpinachJan 14–Feb 4
CilantroFeb 11–Mar 4
KaleJan 28–Feb 11
Collard greensJan 28–Feb 11
TurnipsJan 28–Feb 11
DillFeb 25–Mar 11
CeleryMar 4–Mar 11
CauliflowerFeb 11–Feb 25
LeeksFeb 11–Feb 25
Swiss chardFeb 11–Mar 11
ParsleyFeb 11–Mar 4
Tulip bulbsNov 17–Dec 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
StrawberriesJan 28–Feb 11
AsparagusJan 28–Feb 11Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Jan 21 | Feb 25 | Mar 29 | Nov 10 | Dec 1 | Dec 24 |
| Hard freeze, 28°F | Dec 22 | Jan 20 | Feb 24 | Nov 26 | Dec 16 | Jan 19 |
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 Santa Rosa (USC00047965) sits 7.5 miles from the center of Rohnert Park at 166 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 Rohnert Park, CA?
The average last frost date in Rohnert Park is February 25, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after March 29.
When is the first frost in Rohnert Park?
The first frost in fall usually comes around December 1. One year in ten it arrives before November 10.
How long is the growing season in Rohnert Park?
About 279 days between the average last and first frost.
When should I plant tomatoes in Rohnert Park?
Plant tomato seedlings outside from March 4 to March 18. Start seeds indoors six to eight weeks earlier.
Nearby in California
- Santa RosaFeb 25
- PetalumaFeb 28
- WindsorMar 2
- NovatoJan 11
- NapaFeb 12
- American CanyonMar 5
- San RafaelJan 11
- VallejoJan 17
- HerculesJan 17
- San PabloJan 4
- RichmondJan 4
- BeniciaJan 17