Poway, CA 92186 Frost Dates
Frost dates for Poway, CA, ZIP 92186
The last spring frost here typically falls around 03/04, about 188 days from today. The first fall frost typically arrives around 12/04, about 270 frost-free days later.
The USDA Plant Hardiness Zone Map puts Poway in Zone 11a (40 to 45°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 11a around Poway 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.
Why 03/04 isn't a guarantee
03/04 is the middle of 30 years of NOAA records, not a promise. Plant by 01/29 and you're betting against frost in roughly 9 years out of 10. 04/10 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Poway compares
Poway's growing season runs about 270 days, ranking 5,545 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,965 of 2,555.
Learn more
zone vs. frost date explains why Zone 11a and Poway's frost date answer different questions, and the frost range explains how to read the range around Poway's dates instead of trusting one.