Knoxville, TN 37940 Frost Dates
37940, near Knoxville, TN: the frost window
Typically, the last spring freeze lands around 04/01, roughly 216 days out. Fall's first freeze usually shows up around 11/02, roughly 215 days after the last spring frost.
Knoxville sits in USDA Zone 7b (5 to 10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Knoxville's growing season runs out in roughly 9 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
04/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/17 and only about 1 year in 10 sees frost after that.
Knoxville against the rest of the dataset
Knoxville's growing season runs about 215 days, ranking 14,006 of 40,283 US ZIP codes measured here, longest to shortest. Within TN, it ranks 222 of 770.
Learn more
Two guides worth reading on 37940: local microclimates, on what one yard in Knoxville can differ from the 37940 normal, and zone vs. frost date, on why Zone 7b and Knoxville's frost date answer different questions.