According to the 2023 USDA Hardiness Zone Map Rochester, New Hampshire is in Zones 5b (-15°F to -10°F), 5b (-15°F to -10°F), 6a (-10°F to -5°F) and 6a (-10°F to -5°F). This is a change from the 2012 USDA Hardiness Zone Map which has Rochester in Zones 5a (-20°F to -15°F) and 5b (-15°F to -10°F).