Carlton, MN 55718 Frost Dates
Frost dates for Carlton, MN, ZIP 55718
Typically, the last spring freeze lands around 05/26, roughly 271 days out. The first fall frost typically arrives around 09/23, about 118 frost-free days later.
The USDA Plant Hardiness Zone Map puts Carlton in Zone 4a (-30 to -25°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
Zone 4a around Carlton has about 4 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
05/26 is the middle of 30 years of NOAA records, not a promise. Plant by 05/13 and you're betting against frost in roughly 9 years out of 10. 06/09 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Carlton compares
Carlton's growing season runs about 118 days, ranking 39,214 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 886 of 943.
Learn more
local microclimates explains what one yard in Carlton can differ from the 55718 normal, and zone vs. frost date explains why Zone 4a and Carlton's frost date answer different questions.