Persicaria subsessilis

Hairy Knotweed

Upright to straggling annual or perennial herb, spreading from underground stems. Sparse to dense coarse hairs pressed up the stem. Sheath at leaf base hairy with long hairs on top margin.

Additional information

  • SynonymPolygonum subsessile
  • FamilyPolygonaceae
  • StoreyLower storey
  • Sizeto 1 m high x spreading
  • Plant groupingAquatic & Semi aquatic
  • LeavesNarrow lance-shaped bristly leaves 6-15 cm x 5-15 mm.
  • Flower colourWhite to pale pink
  • Flowering timeJanuary to April
  • FlowersTiny flowers in narrow, terminal dense to loose spikes 3-8 cm long. Stalk sometimes forked at base.
  • Bird attractingLeaves, seeds
  • Butterfly attractingNo
  • Frog habitatYes
  • Growing conditionsMoist soils along margins of watercourses. Full sun, semi-shade.
  • Garden usePlant on dam walls and beside pools and wet areas.
  • Commercially availableIndigenous nursery
  • Conservation statusRestricted distribution within the Shire but locally common.
Photographer/s: Marilyn Bull ©

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