FrostDateCheck

Morristown, MN 55052 Frost Dates

When can you plant in Morristown, MN?

Zone 4b

The last spring frost here typically falls around 05/05, about 250 days from today. The first fall frost typically arrives around 10/05, about 152 frost-free days later.

Morristown sits in USDA Zone 4b (-25 to -20°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.

What to do before the first frost

About 5 weeks of growing season left in Morristown before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

The actual range around Morristown's last frost

05/05 is the middle of 30 years of NOAA records, not a promise. Plant by 04/22 and you're betting against frost in roughly 9 years out of 10. 05/19 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Morristown compares

Morristown's growing season runs about 152 days, ranking 34,811 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 450 of 943.

Learn more

the frost range covers how to read the range around Morristown's dates instead of trusting one. local microclimates covers what one yard in Morristown can differ from the 55052 normal.