Derby, CT 06418 Frost Dates
Frost dates for Derby, CT, ZIP 06418
The last spring frost here typically falls around 04/17, about 232 days from today. The first fall frost typically arrives around 10/27, about 193 frost-free days later.
Derby 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
Zone 6b around Derby has about 9 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 Derby's last frost
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 Derby compares
Derby's growing season runs about 193 days, ranking 19,765 of 40,283 US ZIP codes measured here, longest to shortest. Within CT, it ranks 104 of 391.
Learn more
local microclimates explains what one yard in Derby can differ from the 06418 normal, and zone vs. frost date explains why Zone 6b and Derby's frost date answer different questions.