Pleasanton, CA 94537 Frost Dates
Pleasanton, CA: when does the frost end?
Around 02/15 is the usual last spring frost, about 171 days away. Fall's first freeze usually shows up around 12/02, roughly 292 days after the last spring frost.
Zone 9b (25 to 30°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Pleasanton, not a forecast for this year.
Stretching the season past the first frost
With roughly 14 weeks until Pleasanton's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 02/15 isn't a guarantee
02/15 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/13 and only about 1 year in 10 sees frost after that.
Pleasanton against the rest of the dataset
About 292 days separate Pleasanton's last and first frost, putting it 4,321 of 40,283 ZIP codes nationally. Within CA, it ranks 1,677 of 2,555.
Learn more
Before leaning on 94537's figures: local microclimates explains what one yard in Pleasanton can differ from the 94537 normal, while zone vs. frost date explains why Zone 9b and Pleasanton's frost date answer different questions.