• 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

Heracleum sphondylium


  • Other common names hogweed
    cow parsnip

    giant parsnip
    meadow parsnip

    see more
  • Family Apiaceae

  • Genus Heraclium can be biennial or perennial herbs and include species such as Giant Hogweed, Fennel, Cow Parsley and Ground Elder.

  • Details The hogweed is more diminutive than its infamous cousin, giant hogweed and doesn't carry the same health warnings. Although it may reach 2m in height, it's generally much shorter at 1m. Stems are ridged and hollow, leaves hairy with broad, pinnate lobes. Off-white umbels are borne from midsummer to early autumn. It may be a biennial or monocarpic perennial.


  • Foliage Semi-evergreen

  • Habit Bushy

  • Toxicity Sap may be an irritant. Wear gloves and other protective equipment when handling

  • 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)




  • Full Sun

  • Partial Shade

  • Aspect

  • Exposure


  • Clay


  • Loam


  • MoistureMoist but well-drained

  • SoilClay, Loam

  • pH


  • Ultimate height 1-1.5 metres

  • Ultimate spread

  • Time to ultimate height

How to grow

Cultivation Naturally grows in grassy places of rough grazing, hedgerows and roadsides.

Propagation Propagate by seed

Suggested planting locations and garden types Wildlife Gardens Wildflower meadow

How to care

Pruning None required

Pests Trouble-free

Diseases Trouble-free

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