What plant hardiness zone is Grass Range

Grass Range is located at Fergus County, Montana (MT), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Grass Range 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.

Grass Range, Montana @ wikipedia.