Greenfield, MN 55357 Frost Dates
55357, near Greenfield, MN: the frost window
The last spring frost here typically falls around 04/30, about 245 days from today. Fall's first freeze usually shows up around 10/08, roughly 159 days after the last spring frost.
Zone 4b (-25 to -20°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 Greenfield, not a forecast for this year.
Stretching the season past the first frost
Greenfield'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.
How much risk comes with planting early here
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.
Greenfield against the rest of the dataset
About 159 days separate Greenfield's last and first frost, putting it 32,656 of 40,283 ZIP codes nationally. Within MN, it ranks 255 of 943.
Learn more
Two guides worth reading on 55357: the frost range, on how to read the range around Greenfield's dates instead of trusting one, and local microclimates, on what one yard in Greenfield can differ from the 55357 normal.