Last frost date in Portland, Maine

April 26

Average last frost in spring. In an early year (1 in 10) it's over by April 16; in a late year (1 in 10) it comes after May 7.

October 15

Average first frost in fall. 1 year in 10 it comes by October 2.

Source: NOAA U.S. Climate Normals 1991–2020, station Portland International Jetport (USW00014764), 5.9 miles from Portland, elevation 45 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.

This station is also the nearest one for Saco, South Portland and Westbrook, so their frost dates are the same as Portland's.

What to plant now

Frost dates for Portland, Maine
Early yearAverageLate year
Last frost in springApr 16Apr 26May 7
First frost in fallOct 2Oct 15Oct 30

Frost-free days in an average year: 170

Light frost, frost and hard freeze in Portland
Chance in a yearAverage last in springAverage first in fall
Light frost (36°F)Every yearMay 7Oct 4
Frost (32°F)Every yearApr 26Oct 15
Hard freeze (28°F)Every yearApr 14Oct 27

Nights at 32°F or colder in an average year: 144

What to plant now in Portland

Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.

Nearby in Maine

All 11 places in Maine

Updated