• 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

Agastache 'Tangerine Dreams'

giant hyssop 'Tangerine Dreams'

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
giant hyssop 'Tangerine Dreams'

© RHS

  • Other common names giant hyssop 'Tangerine Dreams'

  • Family Lamiaceae

  • Genus Agastache are herbaceous perennials with simple, aromatic leaves and small 2-lipped tubular flowers in whorls forming dense spikes, in summer and autumn; some are rather tender but can be grown as annual bedding

  • Details 'Tangerine Dreams' is a short-lived perennial, to 90cm tall, that is often grown as an annual. It has triangular leaves and large tiers of numerous orange flowers with contrasting dark, reddish-brown calyces borne over a long period from mid summer to early autumn

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)

    H3

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Can be used as a gap-filler in herb gardens or in sunny, dry places, for example at the base of walls and grows best in sharply-drained soils

Propagation Propagate by seed or propagate by semi-ripe cuttings in late summer for overwintering in a frost-free place

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden Gravel Garden Patio & Container Plants Wildlife Gardens

How to care

Pruning Remove spent flowering spikes through the season to prolong flowering

Pests Generally pest free

Diseases May be affected by powdery mildews

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