Mount Rainier, MD 20712 Frost Dates
20712, near Mount Rainier, MD: the frost window
The last spring frost here typically falls around 03/29, about 213 days from today. Fall's first freeze usually shows up around 11/08, roughly 224 days after the last spring frost.
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 Mount Rainier, not a forecast for this year.
Stretching the season past the first frost
Mount Rainier's growing season runs out in roughly 10 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
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.
Mount Rainier against the rest of the dataset
About 224 days separate Mount Rainier's last and first frost, putting it 11,812 of 40,283 ZIP codes nationally. Within MD, it ranks 120 of 583.
Learn more
Two guides worth reading on 20712: local microclimates, on what one yard in Mount Rainier can differ from the 20712 normal, and zone vs. frost date, on why Zone 7b and Mount Rainier's frost date answer different questions.