Bonne Terre, MO 63628 Frost Dates
Frost dates for Bonne Terre, MO, ZIP 63628
Typically, the last spring freeze lands around 04/13, roughly 228 days out. The first fall frost typically arrives around 10/21, about 191 frost-free days later.
The USDA Plant Hardiness Zone Map puts Bonne Terre in Zone 6b (-5 to 0°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 6b around Bonne Terre has about 8 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.
Why 04/13 isn't a guarantee
04/13 is the middle of 30 years of NOAA records, not a promise. Plant by 03/28 and you're betting against frost in roughly 9 years out of 10. 04/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Bonne Terre compares
At roughly 191 frost-free days, Bonne Terre places 20,753 of 40,283 ZIP codes in this dataset. Within MO, it ranks 722 of 1,129.
Learn more
the frost range explains how to read the range around Bonne Terre's dates instead of trusting one, and local microclimates explains what one yard in Bonne Terre can differ from the 63628 normal.