Westbrook, ME 04038 Frost Dates
Westbrook, ME: when does the frost end?
Around 05/07 is the usual last spring frost, about 252 days away. Fall's first freeze usually shows up around 10/04, roughly 148 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Westbrook in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 5 weeks until Westbrook's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/07 isn't a guarantee
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/18 and only about 1 year in 10 sees frost after that.
Westbrook against the rest of the dataset
Westbrook's growing season runs about 148 days, ranking 35,659 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 310 of 456.
Learn more
Before leaning on 04038's figures: the frost range explains how to read the range around Westbrook's dates instead of trusting one, while local microclimates explains what one yard in Westbrook can differ from the 04038 normal.