Plymouth, MN 55447 Frost Dates
When can you plant in Plymouth, MN?
Around 04/29 is the usual last spring frost, about 244 days away. The first fall frost typically arrives around 10/12, about 163 frost-free days later.
The USDA Plant Hardiness Zone Map puts Plymouth in Zone 5a (-20 to -15°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 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.
How much risk comes with planting early here
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
At roughly 163 frost-free days, Plymouth places 31,282 of 40,283 ZIP codes in this dataset. Within MN, it ranks 127 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 55447 normal.