• 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

Arundo donax

giant reed

  • Other common names giant reed
    Spanish cane

    distaff cane
    great reed
    reed grass
    vineyard cane
    water reed

    see more
  • Family Poaceae

  • Details A. donax is a deciduous rhizomatous perennial, forming spreading clumps of bamboo-like stems to 5m, with arching, strap-shaped blue-green leaves and large terminal purplish flower panicles

  • Plant range Mediterranean

Characteristics

  • Foliage Deciduous

  • Habit Tufted

  • 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

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

  • Exposure Sheltered

Soil

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • Sand

    Sand

  • MoisturePoorly-drained, Moist but well-drained, Well-drained

  • SoilClay, Chalk, Loam, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 4-8 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Easy to grow in any soil but prefers moist situations. To encourage flowering cut back stems after their second year. This plant is listed on Schedule 9 of The Wildlife (Northern Ireland) Order (1985), as amended, as an invasive non-native species. While this does not prevent it from being sold or being grown in gardens in Northern Ireland, the RHS encourages those that do grow it to take great care with managing it and with disposing of unwanted material. The RHS also encourages gardeners in Northern Ireland to find alternative plants to grow to those listed on Schedule 9. For suggested alternative plants see the Plantlife/RHS guide, Gardening without harmful invasive plants

Propagation Propagate by seed, sown in containers in a cold frame in spring or by division in early summer

Suggested planting locations and garden types Flower borders and beds Cottage & Informal Garden Architectural Wildflower meadow

How to care

Pruning Leaves can be cut off when they die back in late autumn

Pests Generally pest free

Diseases Generally disease free

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