Waverly, MN 55390 Frost Dates
55390, near Waverly, MN: the frost window
Around 04/30 is the usual last spring frost, about 245 days away. Fall's first freeze usually shows up around 10/08, roughly 159 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Waverly in Zone 4b (-25 to -20°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
Waverly's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/30 isn't a guarantee
04/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Waverly against the rest of the dataset
At roughly 159 frost-free days, Waverly places 32,671 of 40,283 ZIP codes in this dataset. Within MN, it ranks 259 of 943.
Learn more
Two guides worth reading on 55390: the frost range, on how to read the range around Waverly's dates instead of trusting one, and local microclimates, on what one yard in Waverly can differ from the 55390 normal.