New Castle, IN 47366 Frost Dates
When can you plant in New Castle, IN?
Around 04/27 is the usual last spring frost, about 242 days away. The first fall frost typically arrives around 10/17, about 173 frost-free days later.
The USDA Plant Hardiness Zone Map puts New Castle in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 7 weeks of growing season left in New Castle before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/27 isn't a guarantee
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. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How New Castle compares
New Castle's growing season runs about 173 days, ranking 27,804 of 40,283 US ZIP codes measured here, longest to shortest. Within IN, it ranks 707 of 927.
Learn more
zone vs. frost date covers why Zone 6a and New Castle's frost date answer different questions. the frost range covers how to read the range around New Castle's dates instead of trusting one.