Monroe, SD 57047 Frost Dates
When can you plant in Monroe, SD?
Typically, the last spring freeze lands around 05/03, roughly 248 days out. The first fall frost typically arrives around 10/04, about 153 frost-free days later.
The USDA Plant Hardiness Zone Map puts Monroe 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 5 weeks of growing season left in Monroe 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
05/03 is the middle of 30 years of NOAA records, not a promise. Plant by 04/20 and you're betting against frost in roughly 9 years out of 10. 05/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Monroe compares
About 153 days separate Monroe's last and first frost, putting it 34,646 of 40,283 ZIP codes nationally. Within SD, it ranks 125 of 378.
Learn more
local microclimates covers what one yard in Monroe can differ from the 57047 normal. zone vs. frost date covers why Zone 5a and Monroe's frost date answer different questions.