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How to Grow Penstemon Plants

Guide to Growing Beard Tongue, Cows Tobacco and Balloon Flower

Penstemon plants are natives of Northern America. They can reach from 30 to 90 cm (1 to 3 feet) in height.

They can be grown in the garden as hardy perennials, half hardy annuals, or perennials.

Beard tongue

Penstemon bloom in the summer with tubular lipped flowers; these may be blue, pink, purple, white or yellow. A common name for Penstemon is Beard Tongue.

Penstemon
Penstemon by Creosoteshadow; creative commons.

Penstemon albidus
Penstemon albidus by Matt Lavin.

Commonly Grown Penstemon Species Photographs and Plant Identification

Penstemon eatonii

Penstemon eatonii
Penstemon eatonii (Eaton's Penstemon / firecracker Penstemon), photograph by Andrey Zharkikh; CC.

Penstemon eatonii, commonly known as Eaton's penstemon, is a perennial flowering plant native to the southwestern United States. It features vibrant red or orange tubular flowers that attract pollinators like hummingbirds.

To grow P. eatonii, choose a sunny location with well-draining soil. Sow seeds in early spring or propagate from cuttings. Keep the soil slightly moist but not overly wet. Prune back faded flowers to encourage more blooms. Provide protection from extreme cold temperatures and apply a layer of mulch in winter.

With proper care, you can enjoy the beautiful blooms of Penstemon eatonii in your garden.

Penstemon strictus

Penstemon strictus
Penstemon strictus (Rocky Mountain Penstemon), photograph by Andrey Zharkikh; CC.

Penstemon strictus, commonly known as Rocky Mountain penstemon or strict beardtongue, is a perennial flowering plant native to the Rocky Mountain region of North America. It produces striking blue-violet tubular flowers that attract pollinators like bees and butterflies.

To grow P. strictus, choose a sunny location with well-draining soil. Sow seeds in early spring or propagate from cuttings. Ensure the soil is kept slightly moist but not overly wet. Deadhead faded flowers to promote more blooms. Provide some protection from harsh winter conditions and apply a layer of mulch.

By providing the right conditions, you can enjoy the beautiful blooms of Penstemon strictus in your garden.

Penstemon hirsutus

Penstemon hirsutus
Penstemon hirsutus (Hairy Beard-tongue / Northeastern Beardtongue), photograph by Doug McGrady; CC.

Penstemon hirsutus, commonly known as hairy beardtongue, is a perennial flowering plant native to eastern North America. It displays beautiful clusters of tubular flowers in shades of pink, lavender, or white.

To grow P. hirsutus, select a sunny location with well-draining soil. Plant seeds or propagate from cuttings in spring or fall. Keep the soil moderately moist and provide regular watering during dry periods. Deadhead spent flowers to encourage continuous blooming. Provide some protection from extreme heat and cold.

With proper care, you can cultivate the vibrant and attractive Penstemon hirsutus in your garden.

Penstemon heterophyllus

Penstemon heterophyllus
Penstemon heterophyllus (Bunchleaf Penstemon / Foothill Beardtongue), photograph by Tom Hilton; CC.

Penstemon heterophyllus, commonly known as foothill penstemon, is a perennial flowering plant native to California. It features clusters of tubular flowers in shades of blue, purple, or lavender, adding a vibrant touch to any garden.

To grow P. heterophyllus, choose a sunny location with well-draining soil. Plant seeds or propagate from cuttings in spring or fall. Provide regular watering, allowing the soil to dry slightly between waterings. Deadhead faded flowers to promote more blooms. Mulch around the plant to conserve moisture and suppress weeds.

Protect P. heterophyllus from extreme heat and frost. With proper care, you can enjoy the graceful beauty of foothill penstemon in your garden.

Penstemon spectabilis

Penstemon spectabilis
Penstemon spectabilis (Showy Penstemon / Showy Beardtongue), picture by peganum; CC.

Penstemon spectabilis, commonly known as showy penstemon or royal penstemon, is a perennial flowering plant native to western North America. It showcases stunning spikes of tubular flowers in shades of pink, purple, or magenta, attracting hummingbirds and butterflies to the garden.

To grow P. spectabilis, select a sunny location with well-draining soil. Plant seeds or propagate from cuttings in spring or fall. Keep the soil evenly moist, but avoid overwatering. Deadhead spent flowers to encourage prolonged blooming. Apply a layer of mulch to retain moisture and suppress weeds. Protect the plant from extreme heat and provide adequate air circulation to prevent fungal diseases.

With proper care, you can cultivate the striking beauty of showy penstemon in your garden, creating a vibrant and pollinator-friendly space.

Penstemon Plant Growing and Care Guide

Common Names: Beard Tongue, Balloon Flower, Cows Tobacco. Penstemon: Garden; Phlox; Heller's; Firecracker; Border; Sand; Box; Parachute; White-margined; Bush; Foothill.
Family: Plantaginaceae.
Life Cycle: Hardy annual. Half hardy perennial, hardy perennial.
Height: 4 to 120 inches (10 to 300 cm).
Native: North America. East Asia.
Growing Region: Annual: zones 1 to 10. Perennial: zones 3 to 10.

Flowers: Summer.
Flower Details: Red, white, purple, lilac, yellow, blue, pink. Tubular. Two lips. Distinctive staminode.
Foliage: Herbaceous or shrub. Erect. Lanceolate to oblong.

Sow Outside: Surface. Spring and/or autumn. Spacing 12 to 48 inches (30 to 120 cm).
Sow Inside: Germination time: two to five weeks in the light. Temperature 60°F (16°C). Two months before expected last frost. Transplant outdoors following the last.

Requirements: Full sunlight or light shade. Good drainage. Soil pH 5.5 to 7. Rich soil. Regular watering during prolonged dry periods. Deadhead. Perennials should be cut back to the ground in autumn.
Autumn mulch for perennials once cut back. Winter mulch. Propagate: cuttings can be took from stems in either autumn or in the spring.

How to Grow Beard Tongue and other Penstemon in the Garden

The seeds of Beard Tongue/Penstemon can be sown outdoors in either spring or autumn.

Penstemon plant seeds should be sown on the soil surface.

They like to grow in sunny areas (requires partially shade in hot areas).

Ideally the soil should be fertile and slightly acidic to neutral (pH 5.5 to 7).

The ground that the plant grows in should also have good drainage.

If starting off indoors, then do so about 9 or 10 weeks before the last expected frost of spring.

The seeds should be germinated in the light, at 12 to 18 degrees centigrade (54 to 64°F). Germination should take about 3 to 6 weeks.

Once ready, transfer the young Penstemon plants outside at a spacing of about 30 cm (12 inches; small species) to 75 cm (30 inches; larger varieties).

Caring for Beard tongue and other Penstemon plants in the garden.

To look after Beard tongue and other Penstemon plants, it is best to water regularly and to deadhead the flowers once they have finished blooming.

Once the season has finished in the autumn, cut the plants down to the ground.

It is a good idea to mulch the ground that Penstemon grow in at the same time.

If you require more plants for your garden, they can be propagated by taking stem cuttings. This can be done in either spring or autumn.

Common Questions

How many members does the Penstemon genus contain?

The Penstemon genus is large,and contains around 250 species of perennials.

Do Penstemon members make a good garden or landscaping plant?

Yes, Penstemon are favored for their tubular flowers and their adaptability to various garden conditions. They make excellent border plants.

Which Penstemon species are most frequently grown by gardeners?

Penstemon digitalis, known as Beardtongue, is a species popularly cultivated by gardeners for its white to pinkish flowers.

Are Penstemon plants fragrant?

While some species of Penstemon may have a mild fragrance, they are not generally known for their scent.

What is the perfect location to grow Penstemon?

Penstemon prefer full sun to partial shade and well-drained soil. They can tolerate dry conditions once established.

Is Penstemon invasive in the USA, if so in which states?

Currently, Penstemon species are not considered invasive in the USA.

How do I remove Penstemon plants from my garden?

Penstemon plants can be removed by uprooting the whole plant, ensuring all root parts are also removed to prevent regrowth.

Summary

The Penstemon plant genus, part of the Plantaginaceae family, is a group of herbaceous perennials and shrubs, commonly known as beardtongues. They are admired for their tubular flowers, which come in a variety of colors and attract hummingbirds and butterflies.

Penstemon plants prefer full sun to partial shade and well-draining soil. They are generally planted in spring. Due to their attractive, long-lasting blooms, they are excellent for borders, beds, or rock gardens, adding a splash of color and wildlife interest.

I hope that you enjoyed this guide on how to grow Penstemon plants. You may also enjoy the following Gardener's HQ growing guides: How to grow Purple Bell Vine, Iris plant, Boussingaultia plant, and Collinsia plants.