Lewiston, MN 55952 Frost Dates
When can you plant in Lewiston, MN?
Around 05/08 is the usual last spring frost, about 253 days away. The first fall frost typically arrives around 10/03, about 147 frost-free days later.
The USDA Plant Hardiness Zone Map puts Lewiston in Zone 4b (-25 to -20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 5 weeks of growing season left in Lewiston before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/08 isn't a guarantee
05/08 is the middle of 30 years of NOAA records, not a promise. Plant by 04/25 and you're betting against frost in roughly 9 years out of 10. 05/22 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lewiston compares
Lewiston's growing season runs about 147 days, ranking 35,929 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 609 of 943.
Learn more
local microclimates covers what one yard in Lewiston can differ from the 55952 normal. zone vs. frost date covers why Zone 4b and Lewiston's frost date answer different questions.