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Water Smartweed

Persicaria amphibia

Summary 3

Persicaria amphibia (syn. Polygonum amphibium) is a species of flowering plant in the knotweed family known by several common names, including longroot smartweed, water knotweed, water smartweed, and amphibious bistort. It is native to much of North America, Asia, Europe, and parts of Africa, and it is known elsewhere as an introduced species and sometimes a noxious weed.

Description 4

Family:
Polygonaceae (Buckwheat)

Height:
1 to 3 feet

Leaves:
Lance-shaped leaves are alternately arranged on stem (up to 8 inches long), edges are smooth.

Flower:
Small pink flowers form a spike-like raceme

Bloom time:
June-September

Nicknames:
Swamp Smartweed, Longroot Smartweed, Water Knotweed

Habitat:
Aquatic or terrestrial, ditches, shorelines

Wildlife Benefits:
Flowers are attractive to bees, wasps, flies, butterflies. Seeds are a food source for ducks.

Can I plant this in my garden?
Not typically planted in gardens.

References:
https://www.minnesotawildflowers.info/flower/swamp-smartweed
https://www.illinoiswildflowers.info/wetland/plants/wt_smartweed.html

Range 4

Sources and Credits

  1. (c) Jörg Hempel, some rights reserved (CC BY-SA), http://www.flickr.com/photos/32023375@N06/6945554552
  2. (c) Ramsey-Washington Metro Watershed District, all rights reserved, uploaded by Ramsey-Washington Metro Watershed District
  3. Adapted by Ramsey-Washington Metro Watershed District from a work by (c) Wikipedia, some rights reserved (CC BY-SA), https://en.wikipedia.org/wiki/Persicaria_amphibia
  4. (c) Ramsey-Washington Metro Watershed District, some rights reserved (CC BY-SA)

More Info

iNat Map

Family Polygonaceae
Habit Forb
Life cycle perennial
Flower pink
Origin native
Bloom time (6) June, (7) July, (8) August, (9) September
*sites Lake Phalen, Snail Lake
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