Buellton, CA 93440 Frost Dates
93440, near Buellton, CA: the frost window
Typically, the last spring freeze lands around 01/20, roughly 145 days out. Fall's first freeze usually shows up around 12/19, roughly 335 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Buellton 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
Buellton's growing season runs out in roughly 16 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 01/20 isn't a guarantee
01/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/16 and only about 1 year in 10 sees frost after that.
Buellton against the rest of the dataset
At roughly 335 frost-free days, Buellton places 2,748 of 40,283 ZIP codes in this dataset. Within CA, it ranks 1,242 of 2,555.
Learn more
Two guides worth reading on 93440: zone vs. frost date, on why Zone 9b and Buellton's frost date answer different questions, and the frost range, on how to read the range around Buellton's dates instead of trusting one.