Penstemon ‘Garnet’ (Beardtongue)

One of the longest living Penstemon hybrids, award-winning Penstemon ‘Garnet’ or ‘Andenken an Friedrich Hahn’ is a bushy semi-evergreen perennial renowned for its rich, garnet-red flowers, presenting a dazzling show from early summer to autumn’s first frost. Its deep red, tubular blooms, set against lance-shaped, semi-evergreen leaves, are a beacon for hummingbirds and pollinators.

Penstemon ‘Garnet’: An In-depth Look

Native: This cultivar is not a native species but derived from parent species native to North America.

Plant Type and Habit: It’s a herbaceous perennial with a semi-evergreen habit in milder climates. It has a clump-forming habit that makes it suitable as a border plant.

Size: This Penstemon grows to 24-36 inches tall (60-90 cm) and 12-18 inches wide (30-45 cm), adding lovely vertical lines to the landscape.

Flowers: It boasts deep garnet-red, tubular flowers.

Bloom Time: Expect a spectacular show from early summer through fall.

Foliage: The flowers rise above the foliage mound of lance-shaped, deep green leaves.

Award: Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society.

Uses: This Penstemon is versatile, suitable for border plantings, container gardens, rock gardens, and as part of pollinator-friendly landscapes. Good as cut flowers, too!

Pollinators: Penstemon attracts various pollinators, especially bees and hummingbirds, drawn to the nectar-rich flowers.

Toxicity: Penstemons are not known to be toxic to humans or pets. However, it’s always prudent to prevent ingestion of any non-edible plants.

Deer and Rabbit: A bonus is its resistance to deer and rabbits, a characteristic attributed to the texture and taste of the foliage that these animals generally find unappealing.

Drought: Once established, this Penstemon shows good drought tolerance. While it prefers consistent moisture levels, it can endure short periods of dry conditions, a boon for gardeners in more arid climates.

Invasiveness: Penstemons are not known for being invasive.

Penstemon Growing Tips

Light: Full sun (at least 6 hours of direct sun per day). Tolerates light shade.

Soil: Well-drained soil is crucial. Penstemons prefer rocky or sandy lean soils rather than rich garden loam. Avoid overly moist, poorly drained soils.

Water: Water well until plants are established. Once established, Penstemons tolerate some drought. Allow the soil to dry out between waterings. Over-watering or wet soils can lead to root rot.

Fertilizer: Penstemon plants generally do not require heavy fertilization and can thrive in relatively lean soil conditions. However, providing them with a light application of an organic fertilizer in the fall can help boost their growth and flowering potential.

Pruning: Deadhead spent flowers to encourage continuous blooming. Cut back plants in late autumn or early spring to promote vigorous growth.

Mulching: Mulching Penstemon can help regulate ground temperature and suppress weed growth. Choose a mulch that does not hold water. Use organic materials like shredded bark, compost, or pine straw. Avoiding direct contact with the stems to prevent rot and pest issues.

Propagation: Propagate by softwood cuttings in early summer or semi-hardwood cuttings in midsummer. Propagate by division in spring.

Pests and Diseases: No serious pest or disease issues, but watch for slugs, snails, and nematodes. Fungal diseases can occur in overly wet conditions; ensure good air circulation and avoid overhead watering to prevent issues like powdery mildew, leaf spot, and root rot. Rust can cause small, rust-colored pustules on leaves and stems, leading to defoliation and stunted growth.