Poway, CA 91933 Frost Dates
Poway, CA: when does the frost end?
Typically, the last spring freeze lands around 03/04, roughly 188 days out. Fall's first freeze usually shows up around 12/04, roughly 270 days after the last spring frost.
Zone 10b (35 to 40°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.
Stretching the season past the first frost
With roughly 14 weeks until Poway's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 03/04 isn't a guarantee
03/04 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/29 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/10 and only about 1 year in 10 sees frost after that.
Poway against the rest of the dataset
Poway's growing season runs about 270 days, ranking 5,486 of 40,283 US ZIP codes measured here, longest to shortest. Within CA, it ranks 1,906 of 2,555.
Learn more
Before leaning on 91933's figures: local microclimates explains what one yard in Poway can differ from the 91933 normal, while zone vs. frost date explains why Zone 10b and Poway's frost date answer different questions.