South Portland, ME 04106 Frost Dates
South Portland, ME: when does the frost end?
Typically, the last spring freeze lands around 04/26, roughly 241 days out. Fall's first freeze usually shows up around 10/15, roughly 170 days after the last spring frost.
South Portland sits in USDA Zone 6a (-10 to -5°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 7 weeks until South Portland's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around South Portland's last frost
04/26 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/16 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/07 and only about 1 year in 10 sees frost after that.
South Portland against the rest of the dataset
At roughly 170 frost-free days, South Portland places 28,912 of 40,283 ZIP codes in this dataset. Within ME, it ranks 126 of 456.
Learn more
Before leaning on 04106's figures: the frost range explains how to read the range around South Portland's dates instead of trusting one, while local microclimates explains what one yard in South Portland can differ from the 04106 normal.