Penstemon digitalis (Foxglove Beardtongue)
|Also known as:||Eastern Smooth Beardtongue|
|Habitat:||part shade, sun; average to moist; fields, open woods, roadsides|
|Bloom season:||May - June|
|Plant height:||2 to 5 feet|
|Wetland Indicator Status:||GP: FACW MW: FAC NCNE: FAC|
|MN county distribution (click map to enlarge):|
|National distribution (click map to enlarge):|
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Long-stalked, ascending clusters arising from leaf axils in the upper plant, with 3 to several short-stalked flowers branching at the tip of each cluster. Flowers are about 1 inch long, white to pale pink or lavender, tubular with 5 rounded lobes. The lower lip has 3 lobes nearly equal in size; the upper lip has 2 lobes of equal size and slightly smaller than the lower lobes. Inside the tube are several pinkish or purplish lines, 4 black-tipped stamens hugging the upper part of the tube, a white style, and a sterile stamen with sparse yellow hairs at the tip end.
The floral tube is abruptly inflated from the lower third. The calyx surrounding the flower is green to maroon and has 5 short, spreading, narrowly triangular lobes. Cluster stalks are 1 to 3 inches long and green to maroon. The flower, calyx and flower stalks are all densely covered in short, sticky, glandular hairs.
Leaves and stems:
Basal and lowest stem leaves are somewhat variable, stalked, mostly toothless, mostly hairless, narrowly spatula shaped to oblong to narrowly egg-shaped, 4 to 6 inches long, up to 2½ inches wide, with a blunt or rounded tip, and often somewhat wavy around the edges.
Stem leaves are more lance-like to nearly triangular, pointed at the tip, thin, shiny, finely toothed around the edges, stalkless, somewhat clasping, and tend to be widely spaced with opposite pairs at right angles to the pair above and below. Stems are erect, single or multiple from the base, hairless except in the flower clusters.
Fruit is a teardrop-shaped capsule containing numerous brown, angled seeds.
Foxglove Beardtongue is native to our south and east and the DNR is undecided whether it is native in Minnesota or not. In its native range it's found in meadows, prairies, woodland edges, savannas and along railroads. Herbarium collections in the state have primarily been from along roadsides, which may have been garden escapees and not native populations. It is available in the nursery trade and is sometimes found in restoration plantings. The flowers are similar to White Penstemon (Penstemon albidis) but the latter has much shorter flower stalks arising from the leaf axils and is generally a smaller plant, reaching heights of only 6 to 20 inches. Also similar is Pale Beardtongue (Penstemon pallidus), which has smaller flowers and hairy leaves and stems where Foxglove Beardtongue is hairless except for the flowers.
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Where to buy native seed and plants ↓
- Foxglove Beardtongue plants
- roadside Foxglove Beardtongue (possibly escaped)
- garden-grown Foxglove Beardtongue
- the sticky glands make a good fly trap
- long flower cluster stalks
Photos by K. Chayka taken at Wild River State Park, Chisago County. Photos courtesy Peter M. Dziuk taken in Houston County and in his gardens in Anoka and Ramsey counties.
Have you seen this plant in Minnesota, or have any other comments about it?