What can be said about the perennials Penstemon, commonly called beard tongue? Plenty!
The genus Penstemon has a vast collection of flowering plants that are endemic to North America, with more than 250 species claimed. Every state in our country has native Penstemons growing within its boundaries, and almost all are growing in the western part of our continent. If you wanted to focus on growing a genus of plants, Penstemon gives you a large selection to choose from.
Beard tongues have a wide range of showy plants. If you have a rock garden, there are Penstemons for that. You want a good hummingbird and bee plant; Penstemons will be your wingman. You want a long blooming perennial for your summer garden; you are covered.
Most Penstemons are easy to identify — their eye-catching, tubular flowers with flaring lips, two lips on top and three lips on the bottom.
A few Northwest species grow nearby. From mid to high elevations in the Olympic, Cascade, and Sierra Nevada mountains, Penstemon davidsonii is a low-growing perennial that spreads by creeping, woody stems and can grow in a rock garden.
P. ovatus grows from British Columbia and reaches down into Northwestern Oregon. From Alaska to Oregon, growing from the coast and all the way up high in the Cascades, P. serrulatus is a Penstemon that grows in seeps, near streams, or moist rocky sites. The blue and purple blossoms flower in whorls along the stems.
The border Penstemons also referred to as garden Penstemons come in a large variety of cultivars. Initially, centuries ago in England, four to five species came over from North America that were used in Europe’s hybridization programs. Yet in a 1955 Bulletin of the American Penstemon Society, there came a plea to breed better Penstemons, believing it would make them a more popular genus.
Some hybrids that came out of Penstemon breeding programs are phenomenal, with cultivars ranging from scarlet to purple flowers and even newer varieties with maroon almost black foliage and stems.
Unfortunately, many beard tongues are short lived.
Some of the older cultivars are still here because they perform well in the garden. Penstemon ‘Andenken an Friedrich Hahn’ (also sold as P. ‘Garnet’) has been cultivated since 1918. This old, Dutch Penstemon cultivar is one of the most successful ones in the trade. The tubular, wine-red flowers make it a favorite of hummingbirds. Even without deadheading spent flowers, this cultivar is notably floriferous, blooming all summer up to first frost.
Another favorite variety is Penstemon ‘Sour Grapes’. Flowers of true cultivars have violet and metallic blue hues. Although, which ones sold in the trade are the true cultivars, it is hotly debated amongst enthusiasts. Some claim it’s been many years since the true one was last sold.
Out of the University of Nebraska came a tall, dark, and handsome newcomer to the trade (2008) – Penstemon ‘Dark Towers’. Its deep maroon to almost black foliage had gardeners taking notice. Pale lavender to pink flowers stand out against the dark foliage. When it sends up its spikes of flowers, this perennial is three feet tall and stately. Take a closer look and you notice fine silvery hairs contrasting the dark stems and leaves. The stems tend to be floppy, so staking may be necessary.
Another floriferous and tall penstemon variety bred in England and easily found in nurseries in Kitsap County is Penstemon ‘Blackbird’. Red stems carry the tubular, deep reddish-purple flower and darker buds. Well grown specimens are known to carry up to 75 flowers per stem.
Penstemons are great as cut flowers. Harvest the stems after half of the flowers open. The flowers will last up to a week or more in the vase.
Well-drained soil is necessary for beard tongues. Fertilize at planting time and then forget about adding anymore. Over fertilizing is not recommended or you will end up with too much winter die back and shorter living plants. The less pampering you do, the better life for these perennials. However, fertilizing them will increase their flower production. The tradeoff is having to replace your plants sooner.
Most of these garden selections grow two to four feet tall and look better in massed plantings of three, five, or seven plants.
After the first flush of flowers fade, cut the plant back to side growth. In late summer to early fall a second round of flowers will reward you with more color. Some supplemental watering is necessary during our drought for most cultivars.
— Debbie Teashon
Take a closer look at Penstemon ‘Dark Towers’ and you notice fine silvery hairs contrasting the dark stems and leaves. PenstemonDarkTowers.jpg
Well-grown Penstemon ‘Blackbird’ are known to carry up to 75 flowers per stem. PenstemonBlackBird.jpg
Penstemon ‘Andenken an Friedrich Hahn’s tubular, wine-red flowers make it a favorite of hummingbirds. PenstemonGarnet.jpg
Flowers of true P. ‘Sour Grapes’ cultivars have violet and metallic blue hues. PenstemonSourGrapes.jpg