Caribou, ME 04746 Frost Dates
Frost dates for Caribou, ME, ZIP 04746
Around 05/06 is the usual last spring frost, about 251 days away. The first fall frost typically arrives around 10/02, about 147 frost-free days later.
Zone 4a (-30 to -25°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Caribou, not a forecast for this year.
What to do before the first frost
Zone 4a around Caribou has about 5 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
05/06 is the middle of 30 years of NOAA records, not a promise. Plant by 04/25 and you're betting against frost in roughly 9 years out of 10. 05/21 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Caribou compares
Caribou's growing season runs about 147 days, ranking 35,888 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 328 of 456.
Learn more
the frost range explains how to read the range around Caribou's dates instead of trusting one, and local microclimates explains what one yard in Caribou can differ from the 04746 normal.