Highland Haven, TX 78639 Frost Dates
78639, near Highland Haven, TX: the frost window
Around 03/20 is the usual last spring frost, about 204 days away. Fall's first freeze usually shows up around 11/10, roughly 235 days after the last spring frost.
Zone 8b (15 to 20°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 Highland Haven, not a forecast for this year.
Stretching the season past the first frost
Highland Haven's growing season runs out in roughly 11 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
03/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/11 and only about 1 year in 10 sees frost after that.
Highland Haven against the rest of the dataset
Highland Haven's growing season runs about 235 days, ranking 9,649 of 40,283 US ZIP codes measured here, longest to shortest. Within TX, it ranks 2,034 of 2,558.
Learn more
Two guides worth reading on 78639: the frost range, on how to read the range around Highland Haven's dates instead of trusting one, and local microclimates, on what one yard in Highland Haven can differ from the 78639 normal.