FrostDateCheck

Garwin, IA 50632 Frost Dates

When can you plant in Garwin, IA?

Zone 5a

Typically, the last spring freeze lands around 04/30, roughly 245 days out. The first fall frost typically arrives around 10/09, about 162 frost-free days later.

The USDA Plant Hardiness Zone Map puts Garwin 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 Garwin before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 04/30 isn't a guarantee

04/30 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. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Garwin compares

Garwin's growing season runs about 162 days, ranking 31,843 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 722 of 1,042.

Learn more

the frost range covers how to read the range around Garwin's dates instead of trusting one. local microclimates covers what one yard in Garwin can differ from the 50632 normal.