Water Smartweed – Polygonum amphibium

Discovered this charmer on western edge of the wetlands surrounding Stanley Lake in Seaside, Oregon. It started blooming pink, columnar flowers in early July and is still in bloom at the time of publishing this post.

It’s an interesting plant that grows thick, and in the cluster I found, is about two feet high. I haven’t found it elsewhere — yet.


I find the name rather humorous in 2016, when there are smart phones, smart cars and smart homes. Is this little guy ahead of its time?

The source mentioned that it can grow as an amphibious or aquatic plant; in this case it’s amphibious. There is water nearby, but it’s not growing directly in water.


Although Polygonum amphibium appears to be the best match, according to “Plants of the Pacific Northwest Coast: Washington, Oregon, British Columbia and Alaska” by Pojar and MacKinnon, there are several varieties of smartweed in the region. Hence, it’s possible that my identification is not 100 percent correct. I’m confident that it’s a smartweed of some kind though.


One thing that stands out in the source’s images is that the leaves of my specimen appear to be more narrow, and the flower heads appear to emerge from longer stalks.

Its stalks are hearty, juicy and have a reddish tinge. The flowers are soft pink and appear to have three petals, although it’s hard to tell exactly how many petals there are because the flowers are so small and only a handful are actually in bloom on any given head at one time.

Perspective shot of a 10-15 square foot patch of smartweed

Source: Polygonum amphibium | water smartweed | Wildflowers of the Pacific Northwest. (n.d.). Retrieved August 06, 2016, from http://www.pnwflowers.com/flower/polygonum-amphibium



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s