What plant hardiness zone is Allen

Allen is located at Bennett County, South Dakota (SD), USA.

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

Coldest zone's winter temperature is −25 … -20 °F.

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

Allen, South Dakota @ wikipedia.