Windsor, CA 95436 Frost Dates
95436, near Windsor, CA: the frost window
Around 03/20 is the usual last spring frost, about 204 days away. Fall's first freeze usually shows up around 11/13, roughly 240 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Windsor 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
Windsor's growing season runs out in roughly 11 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Windsor's last frost
03/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/19 and only about 1 year in 10 sees frost after that.
Windsor against the rest of the dataset
Windsor's growing season runs about 240 days, ranking 8,675 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 2,120 of 2,555.
Learn more
Two guides worth reading on 95436: zone vs. frost date, on why Zone 9b and Windsor's frost date answer different questions, and the frost range, on how to read the range around Windsor's dates instead of trusting one.