Hartford, CT 06137 Frost Dates
Frost dates for Hartford, CT, ZIP 06137
Typically, the last spring freeze lands around 04/17, roughly 232 days out. The first fall frost typically arrives around 10/26, about 191 frost-free days later.
The USDA Plant Hardiness Zone Map puts Hartford in Zone 6b (-5 to 0°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
Zone 6b around Hartford has about 8 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 Hartford's last frost
04/17 is the middle of 30 years of NOAA records, not a promise. Plant by 04/01 and you're betting against frost in roughly 9 years out of 10. 05/01 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hartford compares
About 191 days separate Hartford's last and first frost, putting it 20,655 of 40,283 ZIP codes nationally. Within CT, it ranks 167 of 391.
Learn more
zone vs. frost date explains why Zone 6b and Hartford's frost date answer different questions, and the frost range explains how to read the range around Hartford's dates instead of trusting one.