This plant was purchased two summers ago on a whim, from a friend of our daughter who had developed a side gig growing native wildflowers. We were interested in bringing more native flowers to our mixed border and supporting Evan’s interest in growing native plants.

Tall Beardtongue (Penstemon digitalis), which is also called Foxglove Beardtongue, occurs in most states east of the Rockies, but the distribution in individual states may be quite limited as seen in the range map below.

The Penstemon genus is the largest genus of flowering plants in the world with roughly 280 species represented, all occurring in North and South America. We have seen many different Penstemon species on our hikes, from the Florida Panhandle, to the Black Hills of South Dakota, and west to Sequoia and Yosemite National Parks of the Sierra Nevada. They are particularly drought tolerant and therefore quite abundant in the west. I have read that 51 species of Penstemon occur in Nevada alone.

Our specimens have settled in very well amongst the irises and other garden staples.

Its flowers are white with a blush of pink, and covered with fine hairs.

Studying the anatomy of the individual flower, as seen in the photo below, is interesting. What is seen are 4 curving stamens, the male reproductive structure, which are capped with brown anthers, the pollen producing part of the flower. Also noted is a single stigma, the female reproductive organ, which is the white, unadorned filament arcing downwards form the top of the flower tube. Finally, we see the staminode, a sterile, modified stamen that has tan colored hairs on it. It is thought that the staminode’s function is positional, causing pollinators to venture superiorly where their bodies are more likely to acquire pollen from the anthers, or deposit pollen from other flowers on the stigma, increasing the likelihood of successful gene distribution via pollination.

The hairy staminode is the common characteristic of all members of the Penstemon genus, and in some species it is more prominent. The word “penstemon” actually translates to “almost stamen” in Greek. The hairy staminode is also what led to the common name “beardtongue”. In Kentucky there are 4 different species of beardtongue (Tall, Appalachian, Hairy, and Slender-flowered).

Tall Beardtongue’s leaves are somewhat atypical in that the lower leaves on the plant are rather narrow and lance shaped, while the leaves higher on the stem are broader. Ecologically that makes sense, with the large leaves held high to grab more sunlight for photosynthesis.

This photo demonstrates the flower’s progression from bud, to flower, to spent flower, to seedhead.

The seedhead structure is interesting as it features the spent arcing stigma of the female reproductive structure. The seeds, and therefore the seedhead, develop at the base of the stigma.

As with most of our native wildflowers, Tall Beardtongue is an outstanding food source for our native pollinators, as evidence by these photos of a Bumblebee and an acrobatic Bicolored Striped Sweat Bee. In the short time that these photos were taken I witnessed five bee species visiting the flowers.

There are many varieties of Penstemon available from landscape nurseries and most have been developed off Tall Penstemon. The most famous is the beautiful, “Husker Red”, which was the perennial of the year from the American Perennial Society when it was introduced in 1996. It is easily identifiable by the reddish coloration of its stems and leaves. Whenever I have seen it, pollinators are always visiting.

So if you are looking to “go native” with your landscaping, or to add a pollinator bed, Tall Beardtongue, or one of its cultivars, would be a great place to start.

Photos by Peggy Juengling Burns and Patrick Burns, with the exception of the “Husker Red” photo which was taken from the ShrubHub website.