Santa Rosa, CA 95405 Frost Dates
Frost dates for Santa Rosa, CA, ZIP 95405
The last spring frost here typically falls around 02/25, about 181 days from today. The first fall frost typically arrives around 12/01, about 279 frost-free days later.
Zone 9a (20 to 25°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 Santa Rosa, not a forecast for this year.
What to do before the first frost
Zone 9a around Santa Rosa has about 14 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Santa Rosa's last frost
02/25 is the middle of 30 years of NOAA records, not a promise. Plant by 01/21 and you're betting against frost in roughly 9 years out of 10. 03/29 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Santa Rosa compares
About 279 days separate Santa Rosa's last and first frost, putting it 4,853 of 40,283 ZIP codes nationally. Within CA, it ranks 1,782 of 2,555.
Learn more
local microclimates explains what one yard in Santa Rosa can differ from the 95405 normal, and zone vs. frost date explains why Zone 9a and Santa Rosa's frost date answer different questions.