Size and method of spreading:
Foxglove penstemon grows to 3 to 5 feet tall and 1 ½ to 2 feet wide. Foxglove penstemon spreads by self-seeding. The plants also send out short underground stem structures (rhizomes) that produce offsets.
Native geographic location and habitat:
Foxglove penstemon is native to the Eastern and Central United States. C- Value: 4.
Pollinators and wildlife:
The tubular flowers of foxglove penstemon are known to attract bees, beetles, butterflies, hummingbirds, moths, and wasps. Along with attracting honeybees and bumblebees, foxglove penstemon sustains two specialist pollinators: miner bees (Osmia distincta) and pollen-collecting wasps (Pseudomasaris occidentalis). Foxglove penstemon hosts larvae of 13 moth and butterfly species, including the buckeye butterfly.
Leaf description:
Foxglove penstemon has leaves that occur around the base of the plant (basal leaves) and leaves that grow from the stems (cauline leaves). The cauline leaves are typically up to 7 inches long, narrow, and occur in opposite pairs. The lowermost cauline leaves are more rounded toward the tip (oblanceolate to oblong-elliptic), and the higher cauline leaves become more tapered toward the tip (ovate to lanceolate). They are light to medium green, finely toothed around the edges, and stalkless (sessile) to slightly clasping where they attach to the stem.
The basal leaves sometimes have a reddish tint but are primarily light to medium green. They can be narrowly spatula-shaped (spatulate), slightly more tapered at the tip (oblanceolate), or more egg-shaped (ovate to obovate). The edges are smooth or finely toothed, and can be slightly wavy. The basal leaves are often up to 6 inches long and 2 ½ inches wide and are attached by stalks (petioles).
Flower description:
Foxglove penstemon has branched clusters (panicles) of long, tubular white flowers that mature upward from the bottom. The white, petal-like structure (corolla) is swollen upward from the lower third and opens into two lips (bilabiate) at the top that reflex backwards slightly. Violet lines are sometimes present at the throat of the tubular corolla to help guide insect visitors to the flower’s nectar. The bottom lip of the corolla has three lobes at the tip and barely protrudes beyond the upper lip, which is tipped with two lobes. Long, white structures (style and filaments) are visible in the center of the corolla. The filaments are often topped with purplish-black pollen structures (anthers). Around the bases of the corollas are leaflike tubular structures (calyxes) that split into five sharply pointed lobes with tips that are slightly reflexed.
Fruit description:
Dry, ovoid fruit (capsule) is produced by foxglove penstemon. The capsules turn a reddish-brownish-purplish color and split at the top when they are mature. Each capsule contains numerous seeds.
