St. Louis, MO 63180 Frost Dates
Frost dates for St. Louis, MO, ZIP 63180
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.
The USDA Plant Hardiness Zone Map puts St. Louis in Zone 7a (0 to 5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's 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
At roughly 218 frost-free days, St. Louis places 13,164 of 40,283 ZIP codes in this dataset. Within MO, it ranks 68 of 1,129.
Learn more
local microclimates explains what one yard in St. Louis can differ from the 63180 normal, and zone vs. frost date explains why Zone 7a and St. Louis's frost date answer different questions.