FrostDateCheck

Irondale, MO 63648 Frost Dates

Irondale, MO: when does the frost end?

Zone 6b

Around 04/11 is the usual last spring frost, about 226 days away. Fall's first freeze usually shows up around 10/28, roughly 198 days after the last spring frost.

Irondale sits in USDA Zone 6b (-5 to 0°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.

Stretching the season past the first frost

With roughly 9 weeks until Irondale's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.

The actual range around Irondale's last frost

04/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/26 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/30 and only about 1 year in 10 sees frost after that.

Irondale against the rest of the dataset

At roughly 198 frost-free days, Irondale places 18,521 of 40,283 ZIP codes in this dataset. Within MO, it ranks 515 of 1,129.

Learn more

Before leaning on 63648's figures: the frost range explains how to read the range around Irondale's dates instead of trusting one, while local microclimates explains what one yard in Irondale can differ from the 63648 normal.