Frost dates · 1 cities · zones 6a–6a
Maine frost dates, city by city
Portland's median last spring frost is April 26.
| City | Zone | Last frost median | First frost median | Season | Jan → Dec |
|---|---|---|---|---|---|
| Portland | 6a | Apr 26 | Oct 15 | 170 d |
Medians from NOAA NCEI 1991–2020 U.S. Climate Normals at each city's nearest qualifying station; zones from the 2023 USDA Plant Hardiness Zone Map. Open a city for the 1-in-10-year dates, the station, and a planting calendar for every sauce crop.