Audrey Enever: Penstemons are American beauties |

Audrey Enever: Penstemons are American beauties

There's one Routt County wildflower that deserves a place in every perennial garden — the beautiful Rocky Mountain Penstemon (Penstemon strictus). This is the 2-foot blue flower that graces our roadside banks, fields and ditches giving color in June and July. It grows and spreads itself happily into open construction sites, gravel paths and south-facing slopes. This year, there can't be many gardens in Routt County that have not been beautified by their appearance. Added benefits are that most deer will pass it by and the humming birds love it.

Penstemons belong to a drought tolerant genus with more than 270 species, all but one native to North America and many of them at home in the dry, hot summers of the West. They come in a great variety of sizes, flower and leaf color and vary from succulent to woody shrub-like forms. They are named for the five lobes of their delicate tubular flowers with the lobes divided into upper and lower lips. They belong to the same family as the more familiar snapdragon and foxglove.

Native species are augmented by many hybrid varieties (hybrids are distinct plants that result from a cross between two species or varieties). They can occur in the wild but usually are created by plant breeders to provide plants with more desirable characteristics. Hybrids provide gardeners in one region with the characteristics of natives from another region but now tolerant of different weather conditions. Other hybrids have enhanced blooming characteristics. Help also comes to us from the Plant Select® cooperative program of the Denver Botanic Gardens and Colorado State University. Each year, they select plants that thrive in the sunny variable conditions of the Rocky Mountain region and recommend specific varieties for our area. Look for these plants at the local nurseries.

If you'd like to try some penstemons, remember that good drainage is the most important requirement, as they will rot if kept wet.

You can visit the Yampa River Botanic Park to see a variety of penstemons growing in a 6-inch bed of gravel. This is an experimental garden, and people can watch which varieties do well there as compared to similar and other species planted in other conditions in the park.

More information about penstemons can be obtained by joining the American Penstemon Society, which puts out a quarterly magazine, has a seed exchange and a long list of publications. A book by Robert Nold, of Denver, called "Penstemons" covers many of the species and a wealth of botanical information. More information can be found and the website,

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Audrey Enever is a volunteer Master Gardener through the Colorado State University Extension Routt County. She and her husband, Bob, also are the creators of the Yampa River Botanic Park, which was given to the city as a gift to the people of Routt County. Call 970-879-0825 or email with questions.

If you go

The Yampa River Botanic Park will be hosting a free event open to the public. Marcela Ferreyra, a biologist and tourism guide, is a respected expert on the high Andean and steppe floras of Patagonia, and Marcela Sanchez, a botanist born in Buenos Aires city, Argentina, will be speaking at 3:30 p.m. Saturday in the Trillium House.

Marcela Ferreyra will speak about the amazing flora diversity of Patagonia. It has much in common with the Flora of the Rockies including genera and occasionally even similar species.

Penstemon varieties

■ Penstemon strictus (Rocky Mountain Penstemon): our local native — blue/purple flowers on 2-foot spikes, blooms June/July, does well in dry stony areas but also thrives in watered beds. Can be easily moved in early spring, very hardy.

■ Penstemon pinifolius (Pineleaf Penstemon): a shrubby plant with fine pine-like leaves, dainty orangey/red flowers that are 10 to 15 inches, blooms July/August. Develops really woody roots, not easy to move.

■ Penstemon digitalis “Husker Red”: Gets to be about 3 feet high, spikes of white flowers with deep red foliage. Blooms in June and July. Very hardy.

■ Penstemon x mexicali “Red Rocks” and Penstemon x mexicali “Pikes Peak Purple”: both durable hybrids that flower for a long period in mid summer, will be about 15 inches or taller, and like full sun to partial shade.

■ Penstemon eatonii (Firecracker Penstemon): 2 to 3 feet tall, spikes with narrow scarlet flowers. Blooms in June/July and likes heat but needs drainage.

■ Penstemon barbatus: native to the Rocky Mountains, this grows to 3 feet with long loose spikes of red flowers. Blooms in June/July. There are many hybrids based on this native which provide varying heights to 3 feet and many colors from pinks to purples.

■ Penstemon hirsutus “Pygmaeus”: Suitable for rock gardens. Eight inches covered with violet flowers over a long period. Good drainage required.

■ Penstemon caespitosus: suitable for rock gardens, native to the sagebrush areas of Northern Colorado — purple flowers on 3 to 6 inches in height, mats of foliage in May/June. Needs sun and good drainage.

■ Penstemon teucrioides: suitable for rock gardens, native to Gunnison Valley — blue/purple flowers on 2 inches high, mats of foliage June/July.

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