Rockland, ME 04843 Frost Dates
04843, near Rockland, ME: the frost window
Around 04/27 is the usual last spring frost, about 242 days away. Fall's first freeze usually shows up around 10/19, roughly 175 days after the last spring frost.
Rockland sits in USDA Zone 5b (-15 to -10°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
Rockland'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.
Why 04/27 isn't a guarantee
04/27 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 05/09 and only about 1 year in 10 sees frost after that.
Rockland against the rest of the dataset
Rockland's growing season runs about 175 days, ranking 26,856 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 66 of 456.
Learn more
Two guides worth reading on 04843: local microclimates, on what one yard in Rockland can differ from the 04843 normal, and zone vs. frost date, on why Zone 5b and Rockland's frost date answer different questions.