Waterville, ME 04985 Frost Dates
Waterville, ME: when does the frost end?
Typically, the last spring freeze lands around 05/07, roughly 252 days out. Fall's first freeze usually shows up around 10/09, roughly 153 days after the last spring frost.
Waterville sits in USDA Zone 4b (-25 to -20°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
With roughly 6 weeks until Waterville'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 04/27 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/20 and only about 1 year in 10 sees frost after that.
Waterville against the rest of the dataset
About 153 days separate Waterville's last and first frost, putting it 34,487 of 40,283 ZIP codes nationally. Within ME, it ranks 205 of 456.
Learn more
Before leaning on 04985's figures: zone vs. frost date explains why Zone 4b and Waterville's frost date answer different questions, while the frost range explains how to read the range around Waterville's dates instead of trusting one.