St. Ann, MO 63074 Frost Dates
St. Ann, MO: when does the frost end?
Typically, the last spring freeze lands around 04/02, roughly 217 days out. Fall's first freeze usually shows up around 11/04, roughly 215 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts St. Ann in Zone 7a (0 to 5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 10 weeks until St. Ann's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around St. Ann's last frost
04/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/17 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.
St. Ann against the rest of the dataset
St. Ann's growing season runs about 215 days, ranking 14,054 of 40,283 US ZIP codes measured here, longest to shortest. Within MO, it ranks 112 of 1,129.
Learn more
Before leaning on 63074's figures: the frost range explains how to read the range around St. Ann's dates instead of trusting one, while local microclimates explains what one yard in St. Ann can differ from the 63074 normal.