According to the 2023 USDA Hardiness Zone Map Superior, Wisconsin is in Zones 4b (-25°F to -20°F), 4b (-25°F to -20°F), 5a (-20°F to -15°F) and 5a (-20°F to -15°F). This is a change from the 2012 USDA Hardiness Zone Map which has Superior in Zones 4b (-25°F to -20°F).