St. Clair, MO 63077 Frost Dates
When can you plant in St. Clair, MO?
The last spring frost here typically falls around 04/11, about 226 days from today. The first fall frost typically arrives around 10/23, about 194 frost-free days later.
Zone 6b (-5 to 0°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 St. Clair, not a forecast for this year.
What to do before the first frost
About 8 weeks of growing season left in St. Clair before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/11 isn't a guarantee
04/11 is the middle of 30 years of NOAA records, not a promise. Plant by 03/26 and you're betting against frost in roughly 9 years out of 10. 04/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How St. Clair compares
About 194 days separate St. Clair's last and first frost, putting it 19,481 of 40,283 ZIP codes nationally. Within MO, it ranks 634 of 1,129.
Learn more
local microclimates covers what one yard in St. Clair can differ from the 63077 normal. zone vs. frost date covers why Zone 6b and St. Clair's frost date answer different questions.