Plainfield, IN 46231 Frost Dates
46231, near Plainfield, IN: the frost window
The last spring frost here typically falls around 04/12, about 227 days from today. Fall's first freeze usually shows up around 10/27, roughly 196 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Plainfield in Zone 6b (-5 to 0°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Plainfield's growing season runs out in roughly 9 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/12 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/31 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/28 and only about 1 year in 10 sees frost after that.
Plainfield against the rest of the dataset
Plainfield's growing season runs about 196 days, ranking 18,913 of 40,283 US ZIP codes measured here, longest to shortest. Within IN, it ranks 163 of 927.
Learn more
Two guides worth reading on 46231: the frost range, on how to read the range around Plainfield's dates instead of trusting one, and local microclimates, on what one yard in Plainfield can differ from the 46231 normal.