Penstemon digitalis ‘Husker Red’, often called Foxglove Beardtongue, is a robust herbaceous perennial admired for its deep, wine-red foliage that provides garden color from spring until frost. This cultivar produces airy panicles of pure white, tubular flowers in late spring to early summer, which stand in striking contrast to the dark stems and leaves. ‘Husker Red’ is a low-maintenance, long-lived plant that attracts pollinators. Its ease of care and unique coloration make it a popular choice for gardeners seeking reliable performance.
Selecting the Site and Planting
Optimal site selection is foundational to achieving the signature deep maroon foliage of ‘Husker Red’ Penstemon. The plant performs best when situated in a location that receives a minimum of six hours of direct sunlight each day. While it can tolerate some partial afternoon shade, inadequate sun exposure will cause the leaves to lose their desirable dark pigmentation and revert to a less vibrant green color.
This perennial is highly adaptable but has a strong preference for well-draining soil, which is the single most important factor for its long-term health. The root system is susceptible to crown and root rot if left in standing water, so avoid heavy, poorly aerated clay soils. It thrives in average to lean soil compositions, tolerating conditions that are sandy, gravelly, or even nutrient-poor.
When preparing the planting bed, ensure the soil is loose and broken up to a depth equivalent to the root ball’s height. Space individual plants approximately 18 to 24 inches apart to allow for mature spread and to promote necessary air circulation around the basal foliage. This spacing helps prevent moisture buildup that can invite fungal issues later in the season.
Dig a hole twice as wide as the nursery container but only as deep as the root ball. Set the plant so the crown, where the roots meet the stem, sits level with the surrounding soil line. Backfill the hole gently and lightly firm the soil around the base to eliminate any large air pockets. Immediately after planting, water the area thoroughly to settle the soil around the roots and begin the establishment process.
Routine Maintenance and Pruning
Watering practices shift significantly as ‘Husker Red’ Penstemon matures, moving from frequent initial hydration to a drought-tolerant regimen. Newly planted specimens require consistent moisture, meaning deep watering every few days, until the root system is fully established. This period typically lasts for the first growing season.
Once established, the plant thrives on minimal supplemental irrigation. Overwatering is a common mistake that leads directly to root rot, so it is better to err on the side of dryness. Provide deep, infrequent watering only during extended periods of drought, allowing the top several inches of soil to dry out completely between applications.
The plant’s natural preference for lean conditions means it rarely benefits from heavy or routine fertilization. Rich soil or excessive nutrient application, particularly nitrogen, encourages weak, lanky growth and reduces the production of flower spikes. If the soil is very poor, a single light application of a balanced, slow-release fertilizer in early spring is sufficient.
Deadheading, the removal of spent flower stalks, serves two primary purposes: tidiness and encouraging a second flush of blooms. After the main flowering period in early summer, use clean pruners to cut the faded spikes back down to a set of healthy leaves. This action directs the plant’s energy away from seed production and into foliage and root development.
For seasonal cleanup, gardeners can cut back the entire plant by about two-thirds in late autumn, or wait until early spring. Leaving the stalks over winter provides visual interest and modest protection for the crown. In spring, cut the old, dried stems back to within a few inches of the ground as new basal growth begins to emerge.
Troubleshooting Pests and Winterizing
‘Husker Red’ Penstemon is generally pest-resistant. Occasionally, common garden pests such as slugs or aphids may appear, which can be managed with hand-picking or a targeted application of insecticidal soap. Ensuring the plant is properly spaced and receives adequate sunlight minimizes the likelihood of pest problems.
The most frequent disease issue is powdery mildew, which manifests as a white, dusty coating on the leaves, especially in humid conditions or areas with poor air circulation. This fungal problem is best prevented by planting in full sun and avoiding overhead watering. If mildew appears, remove the affected leaves and ensure air flows freely through the plant’s base.
‘Husker Red’ is highly cold-hardy, reliably surviving winters across USDA Hardiness Zones 3 through 8. The plant forms a tight rosette of semi-evergreen foliage at the base that helps it survive freezing temperatures. In milder climates, this basal foliage often retains its maroon coloration throughout the winter.
Winterizing requires little effort beyond the optional fall cutback of spent flowering stems. Avoid applying a thick layer of traditional mulch directly over the plant’s crown, as this can trap excess moisture and lead to rot during winter thaw cycles. If a winter mulch is desired, use a loose, coarse material like gravel or pine needles placed lightly around the crown to maintain well-drained conditions.