Maryland planting zones & frost dates

The 2 Maryland cities on this site fall in zones 7a, 7b. Last spring frost dates range from Mar 29 in Baltimore to Apr 7 in Frederick.

City	Zone	Last frost	First frost	Population
Baltimore	7b	Mar 29	Nov 15	568,271
Frederick	7a	Apr 7	Nov 1	89,537

Frost dates are 30%-risk dates from the nearest suitable NOAA station. Population: Census Vintage 2024 estimates.