Wildflowers
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Pink Knotweed
Polygonum pensylvanicum

Other Names: Pennsylvania Smartweed, Pinkweed

Family
Flower
  • each is ~ 3 mm (1/8 inch), rose or bright pink, sometimes white, and arranged in a thick, upright, elongated, spear-like cluster (1.5-6.5 cm, 0.5-2.5 inches) at the top of a hairy, sticky stem
  • often more than 2 clusters on a stem
  • no petals, 4-6 petal-like sepals
Leaf
  • 10-15 cm (4-6 inches)
  • shiny, long and lance-shaped
  • joints in stem are reddish
  • cylindrical sheath without fringes around base where leaf joins the stem
Location
  • in most parts of North America
  • found in gardens, moist places, fields
Flowering Time
  • May – October
Other
  • plant is usually 20-120 cm (8 inches - 4 feet)
Name Origin
  • N/A
Pink Knotweed

Pink Knotweed Leaf