Common Name: beardtongue
Type: Herbaceous perennial
Family: Plantaginaceae
Zone: 4 to 8
Height: 1.50 to 2.00 feet
Spread: 1.50 to 2.00 feet
Bloom Time: May to July
Bloom Description: Lavendar purple with white lower lips
Sun: Full sun
Water: Dry to medium
Maintenance: Medium
Flower: Showy
Leaf: Good Fall
Attracts: Hummingbirds, Butterflies
Tolerate: Deer, Drought
Culture
Easily grown in average, dry to medium, well-drained soils in full sun. Plants have some tolerance for drought, summer heat and humidity. Avoid wet, poorly-drained soils. Remove spent flowering racemes to prolong bloom. Plants may be cut back to basal foliage after flowering to improve appearance of the planting. Plants in cold winter climates often benefit from a loose winter mulch.
Noteworthy Characteristics
Penstemon is a genus of about 250 species of herbaceous perennials and sub-shrubs which are primarily native to the continental U.S., Canada, Mexico and Guatemala in a variety of habitats ranging from desert to plains to alpine slopes. A large number of hybrids have been developed over the years, but most are of unclear parentage.
The genus name Penstemon likely comes from the Latin paene meaning "almost" or "nearly" and the Greek stemon meaning "stamen". The name may also comes from the Greek penta meaning "five" and stemon meaning "stamen". Both refer to the fifth, sterile stamen (staminode) that characterizes members of this genus.
Penstemons are sometimes commonly called beardtongues because the sterile stamen (staminode) can be hairy.
‘Prairie Twilight’ is a clump-forming penstemon that typically grows 18-22" tall. It is noted for its two-lipped, tubular, lavender purple flowers with white lower lips. Flowers bloom from late spring into early summer in loose upright terminal panicles atop erect, rigid burgundy stems clad with linear medium green stem leaves. Foliage generally retains good color throughout summer. Upper leaves turn bronzy red in fall. 'Prairie Twilight' was developed and introduced by Dale Lindgren at the University of Nebraska. U. S. Plant Patent PP19,893 was issued on April 7, 2009.
Problems
Root rot can occur in wet, poorly-drained soils. Leaf spots, rusts, powdery mildew and Southern blight may also occur. Slugs and snails may chew on the foliage. Watch for spider mites. Deer tend to avoid this plant.
Uses
Sunny areas of borders, rock gardens, cottage gardens and open woodland areas.