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Herbaceous Perennial

Penstemon Rock Candy Blue ('Novapenblu'PBR) (Rock Candy Series)
  • RHS Plants for pollinators

penstemon [Rock Candy Blue]

A compact, upright perennial with lance-shaped green foliage and smallish, long-lasting flared, tubular blue-purple flowers with a white throat which appear from late spring through to the autumn

Synonyms
Penstemon 'Novapenblu'PBR
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Size
Ultimate height
0.1–0.5 metres
Time to ultimate height
2–5 years
Ultimate spread
0.1–0.5 metres
Growing conditions
Chalk
Loam
Sand
Moisture
Well–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Blue Purple Green
Summer Blue Purple Green
Autumn Blue Purple Green
Winter
Position
  • Full sun
  • Partial shade
Aspect

East–facing or South–facing or West–facing

Exposure
Exposed or Sheltered
Hardiness
H3
Botanical details
Family
Plantaginaceae
Native to GB / Ireland
No
Foliage
Deciduous
Habit
Clump forming, Columnar upright
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

Trade

How to grow

Cultivation

Grow in fertile, well-drained soil in full sun or partial shade. In cold areas, protect plant overwinter with a dry winter mulch. See penstemon cultivation for further advice

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
  • Mediterranean climate plants
  • Patio and container plants
  • Wildlife gardens
  • Cut flowers
  • Flower borders and beds
  • Conservatory and greenhouse
Pruning

Deadhead after flowering to maintain vigour and prolong flowering, then cut back to 15cm in late winter or early spring

Pests

May be susceptible to slugs, snails, aphids and leaf and bud eelworms

Diseases

Generally disease-free but may be susceptible to powdery mildews and grey moulds

Get involved

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