Portola, CA 96122 Frost Dates
96122, near Portola, CA: the frost window
Around 06/11 is the usual last spring frost, about 287 days away. Fall's first freeze usually shows up around 09/10, roughly 91 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Portola in Zone 6b (-5 to 0°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
Portola's growing season runs out in roughly 2 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
06/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/25 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 07/02 and only about 1 year in 10 sees frost after that.
Portola against the rest of the dataset
About 91 days separate Portola's last and first frost, putting it 39,900 of 40,283 ZIP codes nationally. Within CA, it ranks 2,534 of 2,555.
Learn more
Two guides worth reading on 96122: the frost range, on how to read the range around Portola's dates instead of trusting one, and local microclimates, on what one yard in Portola can differ from the 96122 normal.