Marietta, OH 45721 Frost Dates
Marietta, OH: when does the frost end?
Typically, the last spring freeze lands around 04/23, roughly 238 days out. Fall's first freeze usually shows up around 10/22, roughly 180 days after the last spring frost.
Zone 6b (-5 to 0°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 Marietta, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Marietta's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Marietta's last frost
04/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/07 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Marietta against the rest of the dataset
Marietta's growing season runs about 180 days, ranking 24,807 of 40,283 US ZIP codes measured here, longest to shortest. Within OH, it ranks 783 of 1,383.
Learn more
Before leaning on 45721's figures: local microclimates explains what one yard in Marietta can differ from the 45721 normal, while zone vs. frost date explains why Zone 6b and Marietta's frost date answer different questions.