• 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

Yucca aloifolia

Spanish bayonet

Spanish bayonet

© RHS 2002

  • Other common names Spanish bayonet
    dagger plant

  • Family Asparagaceae

  • Genus Yucca can be evergreen perennials, shrubs or trees, with dense or loose rosettes of stiff, sword-shaped leaves and tall panicles of bell-shaped flowers

  • Details Y. aloifolia is an evergreen shrub with a simple or sparsely branched stem bearing a terminal rosette of sharp-pointed, sword-shaped leaves, and nodding, bell-shaped white or purple-tinged flowers 8cm across in a terminal panicle

  • Plant range SE USA to Mexico

Characteristics

  • Foliage 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)

    H3

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Chalk, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Under glass grow in loam-based compost keeping just moist in winter. Grow outdoors in containers and over-winter indoors

Propagation Propagate by seed, sown in spring at 19-24° C. Flowers may need hand-pollination to set seed. Rooted suckers can be removed in spring or take root cuttings in winter

Suggested planting locations and garden types Drought Resistant Architectural City & Courtyard Gardens Mediterranean Climate Plants Patio & Container Plants

How to care

Pruning Pruning not normally needed, but damaged leaves and spent flower spikes can be removed as necessary in the spring

Pests Flowers may be attacked by aphids; snails eat the foliage

Diseases Susceptible to a leaf spot

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