FrostDateCheck

Richfield, MN 55423 Frost Dates

When can you plant in Richfield, MN?

Zone 5a

Typically, the last spring freeze lands around 04/23, roughly 238 days out. The first fall frost typically arrives around 10/18, about 176 frost-free days later.

The USDA Plant Hardiness Zone Map puts Richfield 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 7 weeks of growing season left in Richfield 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

04/23 is the middle of 30 years of NOAA records, not a promise. Plant by 04/08 and you're betting against frost in roughly 9 years out of 10. 05/07 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Richfield compares

About 176 days separate Richfield's last and first frost, putting it 26,372 of 40,283 ZIP codes nationally. Within MN, it ranks 39 of 943.

Learn more

zone vs. frost date covers why Zone 5a and Richfield's frost date answer different questions. the frost range covers how to read the range around Richfield's dates instead of trusting one.