FrostDateCheck

Waltham, MA 01773 Frost Dates

When can you plant in Waltham, MA?

Zone 6b

Typically, the last spring freeze lands around 04/28, roughly 243 days out. The first fall frost typically arrives around 10/10, about 165 frost-free days later.

The USDA Plant Hardiness Zone Map puts Waltham in Zone 6b (-5 to 0°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 Waltham before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

The actual range around Waltham's last frost

04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/13 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 Waltham compares

About 165 days separate Waltham's last and first frost, putting it 30,498 of 40,283 ZIP codes nationally. Within MA, it ranks 400 of 712.

Learn more

the frost range covers how to read the range around Waltham's dates instead of trusting one. local microclimates covers what one yard in Waltham can differ from the 01773 normal.