St. Louis, MO 63179 Frost Dates
Frost dates for St. Louis, MO, ZIP 63179
Around 04/01 is the usual last spring frost, about 216 days away. The first fall frost typically arrives around 11/04, about 218 frost-free days later.
St. Louis sits in USDA Zone 7a (0 to 5°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.
What to do before the first frost
Zone 7a around St. Louis has about 10 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
04/01 is the middle of 30 years of NOAA records, not a promise. Plant by 03/14 and you're betting against frost in roughly 9 years out of 10. 04/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How St. Louis compares
About 218 days separate St. Louis's last and first frost, putting it 13,163 of 40,283 ZIP codes nationally. Within MO, it ranks 67 of 1,129.
Learn more
zone vs. frost date explains why Zone 7a and St. Louis's frost date answer different questions, and the frost range explains how to read the range around St. Louis's dates instead of trusting one.