Water Hyacinth - Eichhornia crassipes

The water hyacinth is planta non grata in much of the world where it often jams rivers and lakes with thousands of tons of floating plant matter. In the U.S., water hyacinth is present throughout the southeast, and has been reported as far north as New York and Massachusetts although the plant is reported to not winter over. Eichhornia crassipes grows in all types of freshwaters. They vary in size from a few inches to over three feet tall. They have showy lavender flowers. Their leaves are rounded and leathery, attached to spongy and sometimes inflated stalks. The plant has dark feathery roots.


  • free-floating, except when stranded in the mud; mother plants and daughter plants attached by floating stolons
  • leaves formed in rosettes rise to three feet above the water; leaves entire, ovate, rounded, circular, or broadly elliptic, to 6 in. wide; thick, glossy, waxy green, waterproof; leaf base hear shaped, squared or rounded; veins dense, numerous, fine, longitudinal
  • petioles (leaf stems) floating, creeping; inflated, bulbous, spongy, to 12 in. long
  • multiple (8 to 15) flowers in a single very showy, spike to 12 in. long; spike at top of erect thick stalk to 20 in. long, rising above the leaves; each flower in the flower-spike with six lavender-blue petals (perianths)
  • roots hanging submersed beneath floating leaves, dark purplish to black, feathery, tips with long root caps
  • fruit a capsule, 3-celled, with many seeds; seeds ribbed, formed in submerged, withered flower; fruit and seeds are rarely observed; seeds may produce many seedlings in moderate climates

Water hyacinth found on the Assabet River

Because this species is not yet established in Massachusetts, the best mangement options are prevention and early detection. The International Waterlily & Water Gardening Society compiles a comprehensive list of state-regulated invasive aquatic plants. Check here before buying any plant for water gardening, and never release non-native plants to our local ecosystem.

Various control techniques (mechanical chopping/removal and biological control) have been used in Florida, where the plant is a major problem.

Center for Invasive and Aquatic Plants (University of Florida)
Invasive Plant Atlas of New England