Penstemon heterophyllus 'Heavenly Blue'
penstemon 'Heavenly Blue'
a spreading, woody-based, semi-evergreen perennial to 50cm tall, with narrow, dull, bluish-green leaves. The pinkish-blue flowers, tubular with an open, lobed mouth are about 3cm long and produced in long spikes in summer and autumn
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Green | |||
---|---|---|---|---|
Summer | Blue | Green | ||
Autumn | Blue | Green | ||
Winter | Green |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Plantaginaceae
- Native to GB / Ireland
- No
- Foliage
- Semi evergreen
- Habit
- Bushy
- 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
Accepted
How to grow
Cultivation
Grow in moderately fertile, sharply-drained soil in full sun in a sheltered situation. May need a dry winter mulch in frost prone areas. Will tolerate some shade, but flowers less well. See penstemon cultivation
Propagation
Divide in spring, or take softwood cuttings in early summer or semi-ripe cuttings in midsummer
Suggested planting locations and garden types
- Coastal
- City and courtyard gardens
- Cottage and informal garden
- Gravel garden
- Rock garden
- Wildlife gardens
- Cut flowers
- Wall side borders
- Flower borders and beds
Pruning
Deadhead regularly, or after flowering shorten flowered stems by half, to encourage further flowering. Cut back to about 15cm in spring, after frost as passed, to maintain a compact shape
Pests
Maybe susceptible to slugs, snails, aphids and leaf and bud eelworm
Diseases
May be affected by grey moulds, powdery mildews and fungal leaf spot
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.