New Haven, CT 06503 Frost Dates
When can you plant in New Haven, CT?
Around 04/17 is the usual last spring frost, about 232 days away. The first fall frost typically arrives around 10/27, about 193 frost-free days later.
The USDA Plant Hardiness Zone Map puts New Haven in Zone 7a (0 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 9 weeks of growing season left in New Haven before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/17 isn't a guarantee
04/17 is the middle of 30 years of NOAA records, not a promise. Plant by 04/02 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 New Haven compares
At roughly 193 frost-free days, New Haven places 19,686 of 40,283 ZIP codes in this dataset. Within CT, it ranks 62 of 391.
Learn more
zone vs. frost date covers why Zone 7a and New Haven's frost date answer different questions. the frost range covers how to read the range around New Haven's dates instead of trusting one.