Smartweed is summer annual weed commonly found throughout the midwest.  This weed is commonly found in wet areas including creek, river and pond boarders.  Smartweed has the ability to grow in partially submerged wet areas.  There are several varieties of this broadleaf weed.  The varieties vary in leaf shape and color.  The flowers can also be white, pink and purple in color.  This plant usually blooms from July to October.  The stems of this plant are smooth and are generally reddish to dark pink in color.    The nodes tend to stick out from the stem and create a hump.  The leaves of this plant alternate on the stem.  The stems of the Smartweed grow erect and produce multiple branches from each main stem.  This plant can reach up to 3 feet tall when it is mature.  The stem that holds the flower cluster has small hairs on it.  Upon the top of the stem, a cluster of small flowers is produced.  The flowers grow tightly together to form a solid flower clump.  Smartweed produces small black seeds that are in the shape of tear drops.  One plant can produce over 3,000 seeds.





Treat this plant with a selective broadleaf herbicide when the plant is actively growing.

Similar broadleaf weeds.

  • Lady’s Thumb

Click here for other Smartweed identification sources.