Charlestown, MD 21914 Frost Dates
When can you plant in Charlestown, MD?
Typically, the last spring freeze lands around 04/03, roughly 218 days out. The first fall frost typically arrives around 11/06, about 217 frost-free days later.
Zone 7b (5 to 10°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 Charlestown, not a forecast for this year.
What to do before the first frost
About 10 weeks of growing season left in Charlestown before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/03 isn't a guarantee
04/03 is the middle of 30 years of NOAA records, not a promise. Plant by 03/22 and you're betting against frost in roughly 9 years out of 10. 04/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Charlestown compares
About 217 days separate Charlestown's last and first frost, putting it 13,528 of 40,283 ZIP codes nationally. Within MD, it ranks 309 of 583.
Learn more
local microclimates covers what one yard in Charlestown can differ from the 21914 normal. zone vs. frost date covers why Zone 7b and Charlestown's frost date answer different questions.