Plainfield, WI 54966 Frost Dates
Frost dates for Plainfield, WI, ZIP 54966
The last spring frost here typically falls around 05/10, about 255 days from today. The first fall frost typically arrives around 10/03, about 146 frost-free days later.
Zone 4b (-25 to -20°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 Plainfield, not a forecast for this year.
What to do before the first frost
Zone 4b around Plainfield has about 5 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Plainfield's last frost
05/10 is the middle of 30 years of NOAA records, not a promise. Plant by 04/25 and you're betting against frost in roughly 9 years out of 10. 05/24 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Plainfield compares
About 146 days separate Plainfield's last and first frost, putting it 36,073 of 40,283 ZIP codes nationally. Within WI, it ranks 644 of 860.
Learn more
the frost range explains how to read the range around Plainfield's dates instead of trusting one, and local microclimates explains what one yard in Plainfield can differ from the 54966 normal.