Norwich, CT 06231 Frost Dates
06231, near Norwich, CT: the frost window
Typically, the last spring freeze lands around 04/28, roughly 243 days out. Fall's first freeze usually shows up around 10/13, roughly 167 days after the last spring frost.
Norwich 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.
Stretching the season past the first frost
Norwich's growing season runs out in roughly 7 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/28 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Norwich against the rest of the dataset
Norwich's growing season runs about 167 days, ranking 29,868 of 40,283 US ZIP codes measured here, longest to shortest. Within CT, it ranks 340 of 391.
Learn more
Two guides worth reading on 06231: the frost range, on how to read the range around Norwich's dates instead of trusting one, and local microclimates, on what one yard in Norwich can differ from the 06231 normal.