Forest Lake, MN 55025 Frost Dates
55025, near Forest Lake, MN: the frost window
Around 05/03 is the usual last spring frost, about 248 days away. Fall's first freeze usually shows up around 10/05, roughly 154 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Forest Lake 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
Forest Lake's growing season runs out in roughly 5 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
05/03 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/20 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/19 and only about 1 year in 10 sees frost after that.
Forest Lake against the rest of the dataset
About 154 days separate Forest Lake's last and first frost, putting it 34,227 of 40,283 ZIP codes nationally. Within MN, it ranks 380 of 943.
Learn more
Two guides worth reading on 55025: local microclimates, on what one yard in Forest Lake can differ from the 55025 normal, and zone vs. frost date, on why Zone 4b and Forest Lake's frost date answer different questions.