• 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 foeniculum (Pursh) Kuntze

anise hyssop

anise hyssop

© RHS

  • Other common names anise hyssop

  • Synonyms Agastache anethiodora
    Agastache anisata

  • 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 A. foeniculum is an upright, deciduous perennial forming a clump of leafy stems. The leaves are highly aromatic with a distinct aniseed scent, and have white undersides. The flower spikes are short, with broadly ovate bracts, and are a strong violet blue

  • Plant range N America

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Leaf

  • 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 Exposed or 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 2-5 years

How to grow

Cultivation Grow in sharply drained, fertile soil in full sun

Propagation Propagate by seed or by division in spring

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Cottage & Informal Garden Gravel Garden Mediterranean Climate Plants

How to care

Pruning Remove spent flowering spikes through the season

Pests Generally pest free

Diseases May be affected by powdery mildew

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