Morton, MN 56270 Frost Dates
When can you plant in Morton, MN?
Typically, the last spring freeze lands around 04/30, roughly 245 days out. The first fall frost typically arrives around 10/04, about 157 frost-free days later.
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 Morton, not a forecast for this year.
What to do before the first frost
About 5 weeks of growing season left in Morton before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 and you're betting against frost in roughly 9 years out of 10. 05/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Morton compares
At roughly 157 frost-free days, Morton places 33,434 of 40,283 ZIP codes in this dataset. Within MN, it ranks 309 of 943.
Learn more
zone vs. frost date covers why Zone 4b and Morton's frost date answer different questions. the frost range covers how to read the range around Morton's dates instead of trusting one.