Penstemon aka Beard Tongues are terrific additions to your xeric garden with both native and non-native varieties. The flowers are plentiful, tubular and brilliant colors which attract bees and hummingbirds. There are over 250 types with low growing mat penstemon, shorter ones 8” – 10” tall, and many which grow up to two feet tall. The CSU partnership Plant Select program includes quite a number of penstemon tested to do well in Colorado. Here are some that are fun to scout out in the wild or try growing in our higher elevation area.
The Rocky Mountain Penstemon (Penstemon Strictus) is a native to the Southwest. It is often found in openings of ponderosa pine and spruce-aspen forest at elevations of 7,000-10,000’. It can grow on rocky, infertile, disturbed soils or in home gardens. It grows 18” by 18” or taller with lots of midnight blue flowers and narrow, glossy green leaves.
Bluemist Penstemon (P. virens) is low growing and can spread to carpet gravelly slopes. It has light blue flowers and dark green leaves.
Scarlet Bugler (P. barbatus) and Firecracker Penstemon (P. eatonii) can grow up to 3’ with brilliant red flowers along the stalks. They are hummingbird magnets!
In the higher altitude woods, you may spot Whipple Penstemon (P. whippleanus) with its intensely dark purple flowers and in dry open areas you may see the native Grand Mesa Penstemon (P. mensarum) with cobalt blue flowers in spring.
Blue Buckle Penstemon (P. virgatus) is shorter and long blooming with clusters of blue to blue-purple flowers. It has wide, glossy, dark green basal leaves while the stems have very narrow leaves. It is native to a small area in northern New Mexico and northern Arizona, grows up to 9000’, in xeric conditions, cold winters, and poor soils.
Husker Red Penstemon (P. digitalis Husker Red) grows in a thick mound of reddish foliage with white flowers on erect stalks. It grows up to 8000’, blooms in summer, and may grow 18” wide and 24” tall. In autumn and winter, song birds enjoy its seed.
Pineleaf Penstemon (P. pinifolius) has either fire engine red flowers or light yellow flowers. It grows up to 10” tall with narrow leaves resembling pine leaves. It is native to the Southwest.
If you are excited to try Plant Select, selections include:
Prairie Jewel (P. grandiflorus ‘P010S’) with large flowers from white to rose to deep violet. The leaves are silvery. It is evergreen and long-lived in well drained locations.
Silverton bluemat penstemon (P. linarioides v. coloradoensis) has lavender blue flowers with silvery leaves and reseeds to spread.
Red Rocks penstemon (P. x Mexicali ‘P008S’) with rosy flowers and Pikes Peak Purple (P. x Mexicali ‘P007S’) with mounding dark green leaves and violet purple flowers are hybrids. Bridges Penstemon (P. rostriflorus) with scarlet flowers is native to the Southwest. These three like a somewhat lower elevation like zone 4b or 5.
Whatever you plant, or discover in the woods, look closely at the amazing flower patterns and striping on the petals plus watch for bees and hummingbirds sharing the flowers with you!
Photo credits: Eastern Colorado Wildflowers.com and Dave’s Gardens.com and Irene Shonle.