Indianapolis, IN 46277 Frost Dates
When can you plant in Indianapolis, IN?
Typically, the last spring freeze lands around 04/20, roughly 235 days out. The first fall frost typically arrives around 10/21, about 183 frost-free days later.
Indianapolis sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 8 weeks of growing season left in Indianapolis before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/20 isn't a guarantee
04/20 is the middle of 30 years of NOAA records, not a promise. Plant by 04/06 and you're betting against frost in roughly 9 years out of 10. 05/05 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Indianapolis compares
Indianapolis's growing season runs about 183 days, ranking 23,715 of 40,283 US ZIP codes measured here, longest to shortest. Within IN, it ranks 407 of 927.
Learn more
zone vs. frost date covers why Zone 6b and Indianapolis's frost date answer different questions. the frost range covers how to read the range around Indianapolis's dates instead of trusting one.