Penstemon hartwegii
scarlet beard tongue
P. hartwegii is a bushy semi-evergreen perennial to 70cm in height, with narrow foliage and panicles or racemes of slender bright crimson flowers 4cm in length, marked white in the throat and borne on purple stems
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple | Red White | Green | |
| Autumn | Purple | Red White | Green | |
| Winter | Green |
Position
- Full sun
Aspect
West–facing or South–facing or East–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Plantaginaceae
- Native to the UK
- No
- Foliage
- Semi evergreen
- Habit
- Clump forming
- Genus
Penstemon may be deciduous or evergreen perennials or subshrubs, with simple, narrow leaves and racemes or panicles of bell-shaped or funnel-shaped flowers in summer and early autumn
- Name status
Unresolved
How to grow
Cultivation
Grow in fertile, well-drained soil in a sheltered position in full sun or partial shade. In cold areas, protect plant overwinter with a dry winter mulch
Propagation
Propagate by softwood cuttings in early summer or semi-hardwood cuttings in midsummer. Propagate by division in spring
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Flower borders and beds
Pruning
Deadhead after flowering to maintain vigour, then cut back to base in winter
Pests
May be susceptible to slugs, snails and chrysanthemum eelworms
Diseases
May be susceptible to a downy mildew
Get involved
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