Austin, TX 78718 Frost Dates
78718, near Austin, TX: the frost window
Around 02/20 is the usual last spring frost, about 176 days away. Fall's first freeze usually shows up around 12/03, roughly 291 days after the last spring frost.
Zone 9a (20 to 25°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 Austin, not a forecast for this year.
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 4,403 of 40,283 US ZIP codes measured here, longest to shortest. Within TX, it ranks 565 of 2,558.
Learn more
Two guides worth reading on 78718: local microclimates, on what one yard in Austin can differ from the 78718 normal, and zone vs. frost date, on why Zone 9a and Austin's frost date answer different questions.