Though the Rocky Mountain Penstemon is native to the Rocky Mountain region, the whispery plant is considered to be very adaptable and can be grown all across North America. They rise out of the ground like tall but attractive weeds in wide, bunchy bush-like structures. The Rocky Moutnain Penstemon is herbaceous and spiky, and is a favorite ornamental plant grown by people living in dry areas. It is most widely distributed in wide open areas and forests.