Washington, DC 20422 Frost Dates
Washington, DC: when does the frost end?
Typically, the last spring freeze lands around 03/29, roughly 213 days out. Fall's first freeze usually shows up around 11/08, roughly 224 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Washington in Zone 7b (5 to 10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 10 weeks until Washington's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Washington's last frost
03/29 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/15 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/11 and only about 1 year in 10 sees frost after that.
Washington against the rest of the dataset
About 224 days separate Washington's last and first frost, putting it 11,650 of 40,283 ZIP codes nationally. Within DC, it ranks 178 of 246.
Learn more
Before leaning on 20422's figures: local microclimates explains what one yard in Washington can differ from the 20422 normal, while zone vs. frost date explains why Zone 7b and Washington's frost date answer different questions.