FrostDateCheck

Washington, DC 20434 Frost Dates

When can you plant in Washington, DC?

Zone 8a

Around 03/29 is the usual last spring frost, about 213 days away. The first fall frost typically arrives around 11/08, about 224 frost-free days later.

Zone 8a (10 to 15°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 Washington, not a forecast for this year.

What to do before the first frost

About 10 weeks of growing season left in Washington 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

03/29 is the middle of 30 years of NOAA records, not a promise. Plant by 03/15 and you're betting against frost in roughly 9 years out of 10. 04/11 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Washington compares

About 224 days separate Washington's last and first frost, putting it 11,658 of 40,283 ZIP codes nationally. Within DC, it ranks 186 of 246.

Learn more

local microclimates covers what one yard in Washington can differ from the 20434 normal. zone vs. frost date covers why Zone 8a and Washington's frost date answer different questions.