Petaluma, CA 94937 Frost Dates
Petaluma, CA: when does the frost end?
Typically, the last spring freeze lands around 02/28, roughly 184 days out. Fall's first freeze usually shows up around 11/25, roughly 271 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Petaluma in Zone 10a (30 to 35°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 13 weeks until Petaluma's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
02/28 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/06 and only about 1 year in 10 sees frost after that.
Petaluma against the rest of the dataset
About 271 days separate Petaluma's last and first frost, putting it 5,413 of 40,283 ZIP codes nationally. Within CA, it ranks 1,869 of 2,555.
Learn more
Before leaning on 94937's figures: local microclimates explains what one yard in Petaluma can differ from the 94937 normal, while zone vs. frost date explains why Zone 10a and Petaluma's frost date answer different questions.