Penstemon (10)
Penstemon is a very large genus that is easy to recognize, but not so easy to identify individual species. The flowers are tubular with two lips; the upper lip is two-lobed and the lower is three-lobed. The leaves are opposite without stalks. The flowers can be blue, purple, lavender, pink or red. See Beardtongue, Scarlet Penstemon, Mat Penstemon, Palmer's Penstemon and other Penstemon in Blue Long Clusters. There is a great deal of passion about Penstemon amongst horticulturists on the Internet but the best key I found was from 1915 by Francis Whittier Pennell, Scrophulariaceae of the Central Rocky Mountains. It is charming to read his introduction of traveling along on the Rio Grande Railroad to make his collections. So much has changed and yet so little in 100 years. The American Penstemon Society also has a lot of information.
Rocky Mountain Penstemon
Penstemon strictus
Family:Plantain (Plantaginaceae)
AKA:
One-sided Penstemon, Rocky Mountain
Beardtongue
Photo taken on:
July 6, 2004
Location:
Almont, CO
Life Zones:
Foothills to subalpine
Habitat:
Meadows, slopes, roadsides
Grows to 3 feet tall in showy masses. Flowers range from pale lavender to purple, are hairless and grow on one side of the stem. It is the most common and tallest Penstemon in the Gunnison Valley.
Rocky Mountain Penstemon, below at left, has hairs on the anthers and few or none on its tongue, which distinguishes it from the similar looking Grand Mesa Penstemon, below at right, whose anthers have few hairs and its tongue has long orange hairs at the tip.
Flora of North America reference.
Grand Mesa Penstemon
Penstemon mensarum
Family:
Plantain (Plantaginaceae)
AKA:
Tiger Beardtongue
Photo taken on:
July 4, 2004
Location:
Poverty Gulch, GV, CO
Life Zones:
Montane to subalpine
Habitat:
Disturbed areas, trail-sides
Grows to 18" with non-hairy leaves. Flowers are an intense electric blue or purple-tinged blue and are minutely fuzzy on the outside. They are less than 1" long, shorter than the Rocky Mountain Penstemon. Flowers grow in whorls mostly on one side of the stem.
It is quite common in Mesa, Delta and Gunnison counties but not found in the wild elsewhere and is listed as a Colorado Rare Plant.
Flora of North America reference.
Upland Penstemon
Penstemon saxosorum
Family: Plantain (Plantaginaceae)
AKA:
Upland Beardtongue
Photo taken on:
June 27, 2004
Location:
Almont, CO
Life Zones:
Montane
Habitat:
Gravelly, rocky slopes
Grows 4" to 20" high with smooth, hairless, narrow, lance-shaped leaves. The deep blue flowers are 1" long and grow all around the stem compared to Rocky Mountain Penstemon.
Flora of North America reference.
Narrow-Leaved Penstemon
Penstemon angustifolius
Family:
Plantain (Plantaginaceae)
AKA:
Skyblue Penstemon, Broadbeard Beardtongue
Photo taken on:
May 29, 2016
Location:
Wet Mountains, Eastern CO
Life Zones:
Plains and foothills
Habitat:
Sandy areas, vacant lots,
roadsides
Grows to 20" with stout smooth stems and fleshy, narrow leaves with a prominent mid-rib. Stems and leaves are light green and hairless. The flowers are lavender to bright blue and grow all around the stem. The sterile stamen has orange hairs on its tip.
Flora of North America reference.
Sawsepal Penstemon
Penstemon glaber var. glaber
Family:
Plantain (Plantaginaceae)
AKA:
Western Smooth Beardtongue
Photo taken on:
July 20, 2009
Location:
Wet Mountains, Eastern CO
Life Zones:
Foothills to montane
Habitat:
Open woods, gravelly soils
Can grow to 24" with large leathery bright green leaves opposite on the stem. The blue flowers have pink throats and grow on one side of the stem. The sepals are rounded with a short, sharp tip.
Penstemon glaber has several varieties. They all have bright green, hairless leaves clasping the stem, some are thicker and leathery, shape varies from lance-shaped to almost triangular, some smooth-edged others wavy. Below are two varieties.
Flora of North America reference.
Alpine Sawsepal Penstemon
Penstemon alpinus (P. glaber var. alpinus)
Family:
Plantain (Plantaginaceae)
AKA:
Alpine Penstemon
Photo taken on:
July 5, 2013
Location:
Kenosha Pass, CO 285
Life Zones:
Foothills to subalpine
Habitat:
Gravelly, disturbed soil, roadsides
Grows 4" to 18" east of the Continental Divide but not in the alpine zone, despite its name. Leaves are smooth, lance-shaped and medium green. Showy flowers, about an 1" long, grow on one side of the thick stems. The sepals are oval-shaped and pointed. The sterile stamen is slender and not lobed.
Flora of North America reference.
Brandegee's Penstemon
Penstemon brandegeei (P. glaber var. brandegee)
Family:
Plantain (Plantaginaceae)
AKA:
Photo taken on:
July 10, 2015
Location:
SR 165, San Isabel NF, CO
Life Zones:
Foothills to montane
Habitat:
Gravelly, disturbed soil, road cuts
Grows to 2½ feet, very robust and stockier than P. glaber and P. alpinus. Leaves are broadly lance-shaped and clasp the stem. Flowers are showy, intense blue-purple crowded on one side of the stems and 1½" long. Sepals are oval with a long tip. The sterile stamen is stout with two lobes and sticks out of the throat. Nobody mentions the crinkly-edged leaves.
Flora of North America reference.
Hall's Penstemon
Penstemon hallii
Family:
Plantain (Plantaginaceae)
AKA:
Hall's Beardtongue
Photo taken on:
July 14, 2012
Location:
Paradise Divide, GV, CO
Life Zones:
Alpine
Habitat:
Tundra, rocky, gravelly soils
Grows to 8" with bluish-purple flowers on one side of the stem. Leaves are narrow and entire. It only grows in central and southwest Colorado.
Flora of North America reference.
Front Range Penstemon
Penstemon virens
Family:
Plantain (Plantaginaceae)
AKA:
Green Beardtongue, Blue Mist Penstemon
Photo taken on:
June 15, 2014
Location:
Wet Mountains, Eastern CO
Life Zones:
Foothills to montane
Habitat:
Gravelly areas, wooded slopes
Grows to 12" high from mats of bright green, hairless leaves. Flowers are bright blue to blue violet with a pale throat with maroon stripes and are ½" long. The outside of the flowers has hairs and the beardtongue has orange hairs. Flowers grow all around the stem. It only grows east of the Divide.
Flora of North America reference.
Oneside Penstemon
Penstemon virgatus var. asa-grayi
(Penstemon unilateralis)
Family:Plantain (Plantaginaceae)
AKA:
Oneside Beardtongue
Photo taken on:
July 18, 2016
Location:
CO SR 114, S of Cochetopa Pass
Life Zones:
Foothills to montane
Habitat:
Shady slopes, roadsides
Grows to 2 feet with flowers on one side of the stem. Leaves are long narrow and folded inwards. Flowers are broad with a white throat and strong purple lines, nectar guides. The stamens are white, curved and hairless. The sterile stamen is white, hairless, broader at the tip and extends a little from the throat. This differentiates it from some of the similarly patterned Beardtongues.
Flora of North America reference.