• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Penstemon 'Pensham Blackberry Ice' (Pensham Series)

penstemon 'Pensham Blackberry Ice'

  • Other common names penstemon 'Pensham Blackberry Ice'

  • Synonyms Penstemon 'Blackberry Ice'

  • Family Plantaginaceae

  • 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

  • Details A selection that bears wind-red flowers with purple streaking. Height to around 70cm

Characteristics

  • Foliage Semi-evergreen

  • Habit Bushy

  • Hardiness

    Hardiness ratings

    All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

    • H1a - Under glass all year (>15C)
    • H1b - Can be grown outside in the summer (10 - 15)
    • H1c - Can be grown outside in the summer (5 - 10)
    • H2 - Tolerant of low temperatures, but not surviving being frozen (1 to 5)
    • H3 - Hardy in coastal and relatively mild parts of the UK (-5 to 1)
    • H4 - Hardy through most of the UK (-10 to -5)
    • H5 - Hardy in most places throughout the UK even in severe winters (-15 to -10)
    • H6 - Hardy in all of UK and northern Europe (-20 to -15)
    • H7 - Hardy in the severest European continental climates (< -20)

    H4

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or East-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Loam

    Loam

  • Sand

    Sand

  • MoistureWell-drained

  • SoilChalk, Loam, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height

How to grow

Cultivation Grow in fertile, well-drained soil preferably in full sun. In cold areas, protect plant overwinter with a dry winter mulch

Propagation Propagate by softwood or semi-ripe cuttings in summer

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Cottage & Informal Garden

How to care

Pruning Deadhead after flowering to maintain vigour

Pests Generally trouble-free but maybe attacked by slugs, snails and chrysanthemum eelworms

Diseases May be subject to a downy mildew

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