Hartford, CT 06089 Frost Dates
When can you plant in Hartford, CT?
Around 04/25 is the usual last spring frost, about 240 days away. The first fall frost typically arrives around 10/18, about 172 frost-free days later.
Hartford 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 7 weeks of growing season left in Hartford before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
04/25 is the middle of 30 years of NOAA records, not a promise. Plant by 04/12 and you're betting against frost in roughly 9 years out of 10. 05/10 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hartford compares
Hartford's growing season runs about 172 days, ranking 28,123 of 40,283 US ZIP codes measured here, longest to shortest. Within CT, it ranks 316 of 391.
Learn more
local microclimates covers what one yard in Hartford can differ from the 06089 normal. zone vs. frost date covers why Zone 6b and Hartford's frost date answer different questions.