FrostDateCheck

Poway, CA 92149 Frost Dates

92149, near Poway, CA: the frost window

Zone 10b

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.

The USDA Plant Hardiness Zone Map puts Poway in Zone 10b (35 to 40°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

Poway's growing season runs out in roughly 14 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

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

About 270 days separate Poway's last and first frost, putting it 5,525 of 40,283 ZIP codes nationally. Within CA, it ranks 1,945 of 2,555.

Learn more

Two guides worth reading on 92149: local microclimates, on what one yard in Poway can differ from the 92149 normal, and zone vs. frost date, on why Zone 10b and Poway's frost date answer different questions.