Overview
Penstemon hirsutus 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 hirsutus grows best in full sun, and tolerates most soils and neutral to alkaline pH. Its UK hardiness is rated H3-H5. It is native to SE Canada to Central & E USA.
About
Penstemon hirsutus is a perennial in the plantain family commonly called hairy penstemon. It grows upright with a semi-woody base and a well-branched habit and carries narrow, semi-evergreen leaves. The plant prefers full sun on light, fertile, free-draining soils of neutral to alkaline reaction. It flowers from June to September.
Wikipedia contributors, CC BY-SA 4.0 — Penstemon hirsutus
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 hirsutus originates from south-eastern Canada through the central and eastern United States and is a long-flowering perennial in the Plantaginaceae. It produces narrow, glossy leaves that are semi-evergreen or evergreen and develops an upright, semi-woody base with multiple stems. Plant where it receives full sun on a south- or west-facing site and is sheltered from strong winds. It performs best in light, fertile, free-draining loam or sandy soils with a neutral to alkaline pH; avoid winter-wet situations, as prolonged damp in winter is the main cause of losses. In UK terms it suits H3–H5 (borderline to hardy) locations, so give it the driest, sunniest spot possible where soils remain well drained. Use Penstemon hirsutus in sunny mixed borders, gravel or sand gardens and on slopes or raised beds where free drainage can be guaranteed. Its long season of bloom from June to September helps link late spring into late summer colour and works well where continuity of flowering is required through the summer months.
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 hirsutus 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
- Native to
- SE Canada to Central & E USA
Care notes
Pruning and caring for Penstemon hirsutus
- 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 hirsutus?
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 hirsutus?
Penstemon hirsutus prefers full sun. It suits sheltered positions.
What soil does Penstemon hirsutus need?
Penstemon hirsutus 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 hirsutus?
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 hirsutus hardy in the UK?
Penstemon hirsutus 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 hirsutus?
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
- Penstemon 'Raven'Beardtongues
- Penstemon campanulatusbellflower beardtongue
- Penstemon campanulatus 'Andenken an Hahn'Penstemon
- Penstemon campanulatus 'Evelyn'Beardtongue
- Penstemon campanulatus 'Garnet'Penstemon
- Penstemon campanulatus 'Hidcote Pink'Beardtongue
- Penstemon campanulatus 'Pink Endurance'Beardtongue
- Penstemon cyananthusBlue Penstemon
