FrostDateCheck

Calais, ME 04454 Frost Dates

When can you plant in Calais, ME?

Zone 5a

The last spring frost here typically falls around 05/02, about 247 days from today. The first fall frost typically arrives around 10/15, about 164 frost-free days later.

The USDA Plant Hardiness Zone Map puts Calais in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.

What to do before the first frost

About 7 weeks of growing season left in Calais before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

How much risk comes with planting early here

05/02 is the middle of 30 years of NOAA records, not a promise. Plant by 04/21 and you're betting against frost in roughly 9 years out of 10. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Calais compares

At roughly 164 frost-free days, Calais places 30,953 of 40,283 ZIP codes in this dataset. Within ME, it ranks 133 of 456.

Learn more

local microclimates covers what one yard in Calais can differ from the 04454 normal. zone vs. frost date covers why Zone 5a and Calais's frost date answer different questions.