San Antonio, TX 78225 Frost Dates
78225, near San Antonio, TX: the frost window
Typically, the last spring freeze lands around 02/22, roughly 178 days out. Fall's first freeze usually shows up around 12/02, roughly 284 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts San Antonio in Zone 9a (20 to 25°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
San Antonio'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.
The actual range around San Antonio's last frost
02/22 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/16 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/12 and only about 1 year in 10 sees frost after that.
San Antonio against the rest of the dataset
About 284 days separate San Antonio's last and first frost, putting it 4,657 of 40,283 ZIP codes nationally. Within TX, it ranks 719 of 2,558.
Learn more
Two guides worth reading on 78225: local microclimates, on what one yard in San Antonio can differ from the 78225 normal, and zone vs. frost date, on why Zone 9a and San Antonio's frost date answer different questions.