Yountville, CA 94562 Frost Dates
Yountville, CA: when does the frost end?
Typically, the last spring freeze lands around 02/03, roughly 159 days out. Fall's first freeze usually shows up around 12/04, roughly 306 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Yountville in Zone 9b (25 to 30°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 14 weeks until Yountville's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 02/03 isn't a guarantee
02/03 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/28 and only about 1 year in 10 sees frost after that.
Yountville against the rest of the dataset
Yountville's growing season runs about 306 days, ranking 3,695 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,501 of 2,555.
Learn more
Before leaning on 94562's figures: zone vs. frost date explains why Zone 9b and Yountville's frost date answer different questions, while the frost range explains how to read the range around Yountville's dates instead of trusting one.