What plant hardiness zone is Houlton

Houlton is located at Aroostook County, Maine (ME), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Houlton 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.