Austin, TX 78721 Frost Dates
78721, near Austin, TX: the frost window
The last spring frost here typically falls around 02/20, about 176 days from today. Fall's first freeze usually shows up around 12/03, roughly 291 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Austin 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
Austin'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
02/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 01/23 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/14 and only about 1 year in 10 sees frost after that.
Austin against the rest of the dataset
Austin's growing season runs about 291 days, ranking 4,405 of 40,283 US ZIP codes measured here, longest to shortest. Within TX, it ranks 567 of 2,558.
Learn more
Two guides worth reading on 78721: zone vs. frost date, on why Zone 9a and Austin's frost date answer different questions, and the frost range, on how to read the range around Austin's dates instead of trusting one.