FrostDateCheck

Ruthven, IA 51358 Frost Dates

When can you plant in Ruthven, IA?

Zone 5a

Around 04/27 is the usual last spring frost, about 242 days away. The first fall frost typically arrives around 10/07, about 164 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 Ruthven, not a forecast for this year.

What to do before the first frost

About 6 weeks of growing season left in Ruthven before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

The actual range around Ruthven's last frost

04/27 is the middle of 30 years of NOAA records, not a promise. Plant by 04/11 and you're betting against frost in roughly 9 years out of 10. 05/09 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Ruthven compares

About 164 days separate Ruthven's last and first frost, putting it 31,091 of 40,283 ZIP codes nationally. Within IA, it ranks 609 of 1,042.

Learn more

the frost range covers how to read the range around Ruthven's dates instead of trusting one. local microclimates covers what one yard in Ruthven can differ from the 51358 normal.