According to the 2023 USDA Hardiness Zone Map Lancaster, New Hampshire is in Zones 4a (-30°F to -25°F), 4a (-30°F to -25°F) and 4b (-25°F to -20°F). This is a change from the 2012 USDA Hardiness Zone Map which has Lancaster in Zones 4a (-30°F to -25°F).