Penstemon barbatus var. torreyi (bearded penstemon) — Bushy, upright, semi-woody at the base

Overview

Penstemon barbatus var. torreyi is a bushy, upright, semi-woody at the base perennial in the genus Penstemon, part of the Plantaginaceae family, with semi-evergreen or evergreen; narrow, glossy, mid to dark green foliage. Penstemon barbatus var. torreyi grows best in full sun, and tolerates most soils and neutral to alkaline pH. Its UK hardiness is rated H3-H5. Suggested uses include borders, rock gardens and xeriscaping. It is native to Mexico & S USA.

About

Penstemon barbatus var. torreyi is a perennial Penstemon with upright, multi-stemmed growth and a semi-woody base, notable for a long flowering season from June to September. The plant bears narrow, glossy leaves that are semi-evergreen in mild winters. It favours full sun on light, fertile, free-draining neutral to alkaline soils and a sheltered south- or west-facing aspect.

Wikipedia contributors, CC BY-SA 4.0 — Penstemon barbatus

About the genus

Penstemon, the beardtongues, is a large genus of roughly 280 species of flowering plants native to North America from northern Canada to Central America. It is the largest genus of flowering plants endemic to North America. As well as being the scientific name, penstemon is also widely used as a common name for all Penstemon species alongside beardtongues.

Wikipedia contributors, "Penstemon", CC BY-SA 4.0 — Penstemon

In the garden

Penstemon barbatus var. torreyi is a perennial in the Plantaginaceae, native to Mexico and the southern United States. It produces upright, multi-stemmed clumps with a semi-woody base and narrow, glossy foliage that often remains semi-evergreen where winters are mild. Flowering runs from June to September, offering an extended display through summer into early autumn. Grow it in full sun; choose a south- or west-facing site that is sheltered from prevailing winds. The plant prefers a light, fertile, free-draining loam or sandy soil with a neutral to alkaline pH. Winter wet is the main risk, so avoid heavy, poorly drained ground — many losses are caused by prolonged winter moisture rather than low temperature. Hardiness is H3–H5, which in UK terms ranges from borderline to hardy, so give extra protection in the coldest, most exposed locations. Use Penstemon barbatus var. torreyi in mixed herbaceous borders, gravel or rock gardens and drought-tolerant schemes (xeriscaping) where its long season of interest complements later-summer planting. The narrow glossy leaves provide structural form outside the flowering months and help the plant remain useful in the border for much of the year.

Growing conditions

Best soil and position for Penstemon

Sunlight: Full sun
Soil type: Light, fertile, free-draining loam or sand
Soil pH: Neutral to alkaline
Soil moisture: Well drained; winter wet causes most losses
Aspect: South or west facing
Exposure: Sheltered
UK hardiness: H3-H5

Plant details

Penstemon barbatus var. torreyi size, habit and characteristics

Plant type: Perennial
Habit: Bushy, upright, semi-woody at the base
Foliage: Semi-evergreen or evergreen; narrow, glossy, mid to dark green
Suggested uses: Borders, rock gardens, xeriscaping
Native to: Mexico & S USA

Care notes

Pruning and caring for Penstemon barbatus var. torreyi

Cultivation: Drainage and shelter decide whether a penstemon is perennial or annual in your garden. Plant in spring rather than autumn so the roots establish before winter, and leave the top growth standing until spring as crown protection. Regular deadheading is what sustains the extraordinarily long season. Given the modest hardiness of most cultivars, taking cuttings every summer is sensible insurance.
Pruning: Leave stems intact over winter, then cut back to low healthy buds in mid-spring once frosts have passed. Deadhead continuously through summer, cutting spent spikes to a side shoot.
Propagation: Semi-ripe cuttings taken in late summer root quickly and are the standard method - and the usual replacement for winter losses. Species can be raised from seed.
Pest resistance: Slugs take young spring shoots; capsid bug and eelworm occur but are uncommon.
Disease resistance: Powdery mildew and leaf spot appear on crowded plants. Root rot follows winter waterlogging.

Frequently asked questions

How do I grow Penstemon barbatus var. torreyi?

Drainage and shelter decide whether a penstemon is perennial or annual in your garden. Plant in spring rather than autumn so the roots establish before winter, and leave the top growth standing until spring as crown protection. Regular deadheading is what sustains the extraordinarily long season. Given the modest hardiness of most cultivars, taking cuttings every summer is sensible insurance.

Where is the best place to plant Penstemon barbatus var. torreyi?

Penstemon barbatus var. torreyi prefers full sun. It suits sheltered positions.

What soil does Penstemon barbatus var. torreyi need?

Penstemon barbatus var. torreyi is adaptable and grows happily in most soil types, including light, fertile and free-draining loam or sand. It prefers neutral to alkaline soil. Aim for soil that stays well drained; winter wet causes most losses.

How do I prune Penstemon barbatus var. torreyi?

Leave stems intact over winter, then cut back to low healthy buds in mid-spring once frosts have passed. Deadhead continuously through summer, cutting spent spikes to a side shoot.

Is Penstemon barbatus var. torreyi hardy in the UK?

Penstemon barbatus var. torreyi has an RHS hardiness rating of H3, meaning it is half-hardy, tolerating -5 to 1°C, and may need winter protection in colder areas.

How do I propagate Penstemon barbatus var. torreyi?

Semi-ripe cuttings taken in late summer root quickly and are the standard method - and the usual replacement for winter losses. Species can be raised from seed.

More in the Penstemon genus

Browse all Penstemon →