Poway, CA 91987 Frost Dates
Frost dates for Poway, CA, ZIP 91987
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.
Zone 9b (25 to 30°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 Poway, not a forecast for this year.
What to do before the first frost
Zone 9b 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.
How much risk comes with planting early here
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 5,493 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,913 of 2,555.
Learn more
zone vs. frost date explains why Zone 9b 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.