Penstemon digitalis

Biological Name:

Penstemon digitalis (Penstemon-digitalis)

Natural Habitat:

Penstemon-digitalis, also known as foxglove beardtongue, is native to North America and is found in a variety of habitats, including prairies, meadows, and open woods.


Penstemon digitalis is a type of flowering plant that is commonly found in fields and other grassy areas. It is a member of the Plantaginaceae family which also includes plants such as foxgloves and plants. Penstemon digitalis is an annual or perennial plant that produces small white or pink flowers and clusters of seeds. The plant is often used as a cover crop to improve soil health and suppress weeds. It is also known for its ability to tolerate a wide range of growing conditions including wet or dry soils. In some areas penstemon digitalis is considered a weed because of its ability to invade cultivated areas and cause allergies and other health problems.

Frequently Asked Questions (FAQs)

Q: Is Penstemon digitalis invasive?
A: Becomes invasive. Digitalis pushes its seeds into wild lands and out-competing native species that support native wildlife and natural beneficial insects that keep those we consider pests at bay.

Q: Does Digitalis grow back every year?
A: complete growing guide Our native foxgloves, Digitalis purpurea, are biennial meaning that you sow them one year and they flower the next, but they seed themselves so freely they appear to be perennial.

Q: Do you cut back Digitalis after flowering?
A: Deadhead spent blooms after flowering to encourage a second flush, or let them self seed over the garden. Biennial types can be dug up after they have set seed, but perennial foxgloves should be cut back for autumn, ready to bloom again the following year. More on growing foxgloves: Six plants to grow with foxgloves.

Q: Does penstemon reseed itself?
A: Growing Penstemon is straightforward, as they are extremely resilient when well-matched to their planting site, and are excellent naturalizing plants when encouraged to re-seed themselves.

Q: Is penstemon the same as foxglove?
A: Penstemon digitalis, commonly called foxglove beardtongue, is a clump-forming, Missouri-native perennial which typically grows 3-5′ tall and occurs in prairies, fields, wood margins, open woods and along railroad tracks.

Q: Is it OK to touch foxglove?
A: “It is certainly not dangerous to anybody or animals to touch

if foxgloves grow in your midst be sure to keep an eye on young children or pets who tend to put things in their mouths
just in case.”

Q: How do you care for a Penstemon digitalis?
A: CULTURAL & MAINTENANCE NEEDS: Penstemon digitalis flourishes in sunny sites with wet or moist acid loamy soil. Plants tolerate clay loam, sand, alkaline pH, heat, drought, part sun and dry shade. Deadheading to remove dried stalks in fall will allow the lovely purplish rosettes to function as a winter groundcover.

Q: Is Penstemon digitalis toxic to humans?
A: A North American native, foxglove beardtongue (Penstemon digitalis) resembles foxgloves but is not poisonous.

Q: Is Penstemon plant poisonous to dogs?
A: Penstemon ‘Rubicundus’ has no toxic effects reported.

Q: Is Penstemon digitalis Evergreen?
A: The foliage of this robust perennial can be semi-evergreen in warm winter areas. The flowers are followed by small capsules which often turn reddish in late summer, dry brown in fall, and hold well into winter.

Q: Does Penstemon like sun or shade?
A: Light preference: Full sun to part shade. Varieties with purple or reddish leaves will exhibit the best foliage color when grown in direct sunlight.

Q: What can I plant with Penstemon digitalis?
A: Penstemon digitalis ‘Husker Red’ will perform well if given average soil, good drainage, and full sun conditions. Companions for this drought tolerant gem include Hydrangea quercifolia, Fothergilla gardenii, Baptisia ‘Purple Smoke’, and Rudbeckia fulgida ‘Goldsturm’.

Q: How long do penstemon plants last?
A: After about five years, penstemons often need replacing as they become woody and flower less well.

Q: Does penstemon multiply?
A: After the plants have bloomed, penstemons will produce copious amounts of seed. If you are hoping to have your penstemon plants freely seed around your garden, make sure to leave a few stalks on the plants so they can fully ripen and disperse.

Q: Where should I plant penstemon?
A: Grow penstemons in moist but well-drained soil in full sun to partial shade. Mulch annually with well-rotted manure or leaf mould, and feed weekly in summer. Penstemons are short-lived perennials that can suffer in winter. To avoid losses, pruning penstemon is best done in spring.

Q: Is Penstemon digitalis poisonous to dogs?
A: ANSWER: Although Penstemon is not listed on the ASPA guide to toxic and non-toxic plants,there is information online that Penstemon does accumulate Selenium and additional information that an excess of Selenium is not healthy for pets. So it would be wise to keep your dogs away from Penstemon if you can.

Q: How big do penstemon plants get?
A: Most penstemons are 1 to 3 feet tall, but Palmer’s penstemon can grow up to 6 feet, giving you options for the middle and back of the border. Keep the penstemon flowerbed weeded regularly. A 3-inch layer of organic mulch can help to control weeds, and rock mulch is also a suitable choice.

Q: Should penstemon be cut back?
A: Penstemon doesn’t require too much pruning when compared to some other plants, but it’s still a good idea to cut them back when you notice they’re becoming overgrown, or you want to remove wilting foliage/flowers to encourage new growth.

Q: What do you do with penstemons in the winter?
A: Given good drainage all penstemons should survive most winters, but they must keep most of their foliage over winter.

Q: Do penstemon come back every year?
A: Most penstemons are herbaceous perennials, but some hybrid strains are half-hardy and better suited for use as annual bedding plants.

Q: Do penstemons come back each year?
A: Penstemons are short-lived perennials that can suffer in winter. To avoid losses, pruning penstemon is best done in spring. It’s also a good idea to take summer cuttings to prevent winter losses.

Q: Do penstemons bloom twice?
A: If you are hoping to have your penstemon plants freely seed around your garden, make sure to leave a few stalks on the plants so they can fully ripen and disperse. Otherwise, you can remove spent blooms to encourage a second wave of flowers.

About the author

Samuel is a gardening professional and enthusiast who has spent over 20 years advising homeowners and farm owners on weed identification, prevention and removal. He has an undergraduate degree in plant and soil science from Michigan State University.