What plant hardiness zone is Rocky Mountain Natl Park

Rocky Mountain Natl Park is located at Grand County, Colorado (CO), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Rocky Mountain Natl Park 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.