Indianapolis, IN 46225 Frost Dates
Indianapolis, IN: when does the frost end?
Typically, the last spring freeze lands around 04/20, roughly 235 days out. Fall's first freeze usually shows up around 10/21, roughly 183 days after the last spring frost.
Zone 6b (-5 to 0°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 Indianapolis, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Indianapolis's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/20 isn't a guarantee
04/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/06 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/05 and only about 1 year in 10 sees frost after that.
Indianapolis against the rest of the dataset
At roughly 183 frost-free days, Indianapolis places 23,707 of 40,283 ZIP codes in this dataset. Within IN, it ranks 399 of 927.
Learn more
Before leaning on 46225's figures: the frost range explains how to read the range around Indianapolis's dates instead of trusting one, while local microclimates explains what one yard in Indianapolis can differ from the 46225 normal.