Plymouth, MN 55483 Frost Dates
When can you plant in Plymouth, MN?
Typically, the last spring freeze lands around 04/29, roughly 244 days out. The first fall frost typically arrives around 10/12, about 163 frost-free days later.
Zone 5a (-20 to -15°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 Plymouth, not a forecast for this year.
What to do before the first frost
About 6 weeks of growing season left in Plymouth before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/29 isn't a guarantee
04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Plymouth compares
Plymouth's growing season runs about 163 days, ranking 31,291 of 40,283 US ZIP codes measured here, longest to shortest. Within MN, it ranks 136 of 943.
Learn more
the frost range covers how to read the range around Plymouth's dates instead of trusting one. local microclimates covers what one yard in Plymouth can differ from the 55483 normal.