Perennial in USDA zones 4-9. A long-lived penstemon, Rocky Mountain Blue enhances the garden for twelve months of the year. Its exquisite blue-violet flower spikes bloom for about a month in early summer, followed by satiny brown teardrop seedpods. In winter, the plants’ evergreen basal rosettes turn from green to reddish purple. An easy to grow, very hardy and drought tolerant choice for wildflower plantings and formal garden borders.