FrostDateCheck

Rochester, NH 03866 Frost Dates

When can you plant in Rochester, NH?

Zone 6a

Around 04/30 is the usual last spring frost, about 245 days away. The first fall frost typically arrives around 10/09, about 161 frost-free days later.

The USDA Plant Hardiness Zone Map puts Rochester in Zone 6a (-10 to -5°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 6 weeks of growing season left in Rochester 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

04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/18 and you're betting against frost in roughly 9 years out of 10. 05/13 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Rochester compares

Rochester's growing season runs about 161 days, ranking 31,960 of 40,283 US ZIP codes measured here, longest to shortest. Within NH, it ranks 62 of 260.

Learn more

local microclimates covers what one yard in Rochester can differ from the 03866 normal. zone vs. frost date covers why Zone 6a and Rochester's frost date answer different questions.