Frost dates in Maine

Across Maine's 82 NOAA stations with a frost every year, the typical last spring frost ranges from April 21 at Woodland (120 feet above sea level) to June 2 at Allagash (600 feet above sea level). The middle station's date is May 8.

Look up your ZIP code

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Last frost across Maine

The frost-free season runs from 102 days at Allagash to 185 days at Woodland.

These are typical dates: in half of springs the last frost comes later. Each place's page, and each ZIP code lookup, also gives the late-year date, after which only 1 spring in 10 has a frost. That's the safer date for tender plants.

Frost dates for Maine's larger places

PlaceLast spring frostFirst fall frostSeasonZone
BangorMay 4October 4152 days5a
LewistonApril 25October 19177 days5b
PortlandApril 26October 15170 days6a

Typical (1-in-2) dates. Each place's page has the early and late years, a planting calendar and a printable planner. Zones are for the ZIP code nearest each place's center.

Hardiness zones in Maine

Maine's 479 ZIP codes in the USDA list fall in zones 3b to 7a: 3b (under 1 percent), 4a (5 percent), 4b (6 percent), 5a (32 percent), 5b (31 percent), 6a (23 percent), 6b (2 percent) and 7a (under 1 percent). Compared with the 2012 map, 58 percent of them moved to a warmer half zone (17 by a full zone or more), 41 percent stayed the same and 6 moved to a colder one.

A hardiness zone is about the coldest night of winter, which decides which shrubs, trees and perennials survive. Frost dates are about spring and fall, which decide when to plant. You need both. Read more about what the zones mean and what changed in 2023.

Every NOAA station in Maine

All 82 stations in Maine with frost statistics in NOAA's 1991 to 2020 normals, from A to Z. Station names are usually a town, an airport, or a distance and direction from a town. Find one near you and at a similar elevation.

StationElevation (feet)Last spring frostFirst fall frostSeason (days)
Acadia NP470April 27October 22177
Allagash600June 2September 15102
Andover 2820May 19September 25129
Augusta State Airport350April 27October 16172
Bangor International Airport150May 4October 4152
Barnard540May 12October 1141
Bath30May 10October 6149
Belfast20May 7October 5151
Bethel 6 SSE790May 6October 2147
Brassua Dam1,070May 23September 29128
Bridgewater420May 25September 18115
Bridgton 3 NW510May 5October 5151
Brunswick NAS70May 2October 10160
Cape Neddick150May 1October 14165
Caribou Municipal Airport620May 7October 1143
Clayton Lake1,000May 30September 13106
Corinna300May 8October 3148
Danforth480May 25September 24119
Dover-Foxcroft WWTP370May 15September 28134
Durham140May 15October 2139
E Sangerville640May 6October 7153
E Surry100May 8October 9152
East Hiram530May 12October 1140
Eastport90April 29October 25178
Eustis1,260May 24September 21118
Farmington400May 16September 26130
Fort Kent610May 23September 24121
Frenchville Aroostook Airport990May 6October 2147
Fryeburg E Slopes Airport450May 17September 25128
Gardiner130May 1October 11163
Grand Lake Stream290May 4October 10157
Gray380April 28October 19172
Greenville Maine Forestry Service1,040May 7October 9153
Harmony320May 11October 1141
Hartford710May 6October 3148
Hollis310May 14September 30136
Houlton 5 N390May 19September 23125
Houlton International Airport480May 27September 18115
Jackman1,210May 26September 23119
Jonesboro190May 3October 9158
Kennebunkport20May 9October 3146
Lewiston180April 25October 19177
Limestone 4 NNW740May 16September 24129
Lincoln Sanitary District/wtp190May 4October 6153
Livermore Falls 1 E380May 11September 29138
Long Falls Dam1,160May 13September 30138
Madison220May 8October 5149
Middle Dam1,460May 19October 1133
Millinocket360May 9October 5147
Millinocket Municipal Airport410May 8October 1143
Millinocket Wastewater360May 17September 29133
Moosehead1,040May 13September 30137
New Sharon480May 7October 2146
Newcastle210April 27October 18172
Old Town 2 W130May 13September 28137
Orono110May 1October 6157
Patten 2820May 13September 30138
Pittston Farm1,100May 20September 23123
Pittston Farms Nepp1,080May 21September 21122
Poland570May 3October 7157
Portland International Jetport50April 26October 15170
Presque Isle600May 14September 26131
Rangeley1,530May 23September 27127
Rangeley 2 NW1,780May 23September 24123
Robbinston110May 5October 13160
Rumford 1 SSE630May 4October 6155
Rumford 6 SW630May 12September 29139
Sanford 2 NNW290May 16September 30136
Sebec Lake380May 16October 1135
Tenants Harbor20April 27October 25178
Topsfield 2620May 6October 8155
Turner560May 1October 10162
Van Buren 2460May 23September 26125
Vanceboro No 2420May 13October 1139
W Rockport 1 NNW360April 27October 19175
Waterville Treatment Plant70May 2October 10159
Wesley410May 2October 15164
West Buxton 2 NNW220May 7October 4148
Westport Island90April 28October 21175
Windham 2 NW440April 30October 20172
Wiscasset Airport70May 8October 7151
Woodland120April 21October 26185

Typical (1-in-2) dates at 32°F. For the early and late years, and a planting calendar built from your own dates, look up your ZIP code.