According to the 2023 USDA Hardiness Zone Map Portage County, Ohio is in Zones 6a (-10°F to -5°F) and 6b (-5°F to 0°F). There is no change from the 2012 USDA Hardiness Zone Map which has Portage County in also in Zones 6a (-10°F to -5°F) and 6b (-5°F to 0°F).