• 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

Ferocactus viridescens

coast barrel cactus

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
coast barrel cactus

© � RHS 1959

  • Other common names coast barrel cactus
    keg cactus

  • Genus Ferocactus are spherical to columnar cacti with prominent ribs bearing spiny areoles, the spines sometimes hooked, and funnel-shaped flowers in summer

  • Family Cactaceae / Cactaceae

  • Details F. viridescens is a cactus with bright green, usually solitary, globose or cylindric, shallowly ribbed stems to 30cm in height; central spines yellow, curved, to 5cm in length. Flowers 5cm, green or tinged with red

  • Plant range USA, Mexico

Characteristics

  • Foliage Evergreen

  • Habit Clump-forming

  • 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)
    Old hardiness ratings

    While we update our systems with the new hardiness ratings you may still see old hardiness ratings in your search results. These are denoted as 'Old'.

    • H1 - Requires heated glass
    • H2 - Requires unheated glass
    • H3 - Hardy outside in some regions of the UK
    • H4 - Hardy throughout the UK
    • H1 + H3 - Requires heated glass but may be grown outside in summer

    For full details of the hardiness ratings see

    see more

    H1c

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or East-facing or North-facing

  • Exposure Sheltered

Soil

  • Chalk

    Loam

  • Chalk

    Sand

  • MoistureWell-drained

  • SoilLoam, Sand

  • pHNeutral, Alkaline, Acid

Size

  • Ultimate height

    0.1-0.5 metres

  • Ultimate spread

    0.1-0.5 metres

  • Time to ultimate height

    10-20 years

How to grow

Cultivation Grow under glass in a standard cactus compost, in bright, filtered light, with low humidity. When in growth water moderately and feed every two or three weeks with a balanced liquid feed. Keep almost dry in the winter

Propagation Propagate by seed sown at 10 - 20�C in early spring

Suggested planting locations and garden types Low Maintenance Patio & Container Plants

How to care

Pruning No pruning required

Pests May be attacked by mealybugs

Diseases Generally disease free

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