Richfield, MN 55417 Frost Dates
55417, near Richfield, MN: the frost window
The last spring frost here typically falls around 04/23, about 238 days from today. Fall's first freeze usually shows up around 10/18, roughly 176 days after the last spring frost.
Richfield sits in USDA Zone 5a (-20 to -15°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
Richfield's growing season runs out in roughly 7 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/23 isn't a guarantee
04/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/07 and only about 1 year in 10 sees frost after that.
Richfield against the rest of the dataset
About 176 days separate Richfield's last and first frost, putting it 26,370 of 40,283 ZIP codes nationally. Within MN, it ranks 37 of 943.
Learn more
Two guides worth reading on 55417: zone vs. frost date, on why Zone 5a and Richfield's frost date answer different questions, and the frost range, on how to read the range around Richfield's dates instead of trusting one.