What plant hardiness zone is Northumberland

Northumberland is located at Coos County, New Hampshire (NH), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Northumberland is 4a by the USDA scale.

Coldest zone's winter temperature is −30 … -25 °F.

Plants of 4a USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 4a USDA.

Northumberland, New Hampshire @ wikipedia.