• 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

Hyssopus officinalis

hyssop

  • Other common names hyssop

  • Family Lamiaceae

  • Genus Hyssopus can be herbaceous perennials or evergreen shrubs, with linear, aromatic leaves and whorls of tubular, 2-lipped flowers in spike-like inforescences

  • Details H. officinalis is a compact, spreading, semi-evergreen sub-shrub with erect shoots bearing aromatic, linear leaves and terminal spikes of whorled, 2-lipped, tubular blue flowers in summer and early autumn

  • Plant range SE Europe

Characteristics

  • Foliage Semi-evergreen

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or West-facing

  • Exposure Sheltered or Exposed

Soil

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilChalk, Loam

  • pHAlkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in fertile, well-drained, alkaline to neutral soil in full sun

Propagation Propagate by seed or softwood cuttings in summer

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

How to care

Pruning Pruning group 10 in mid-spring

Pests Can get leafhoppers

Diseases Generally disease free

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