Water hyacinth has not been found in the wild in Washington but it is sold as an ornamental plant in garden stores in the state. Although it is thought that water hyacinth cannot survive Washington's winters, its presence as an ornamental makes it possible for escape and growth in the wild under the right conditions. Water hyacinth reproduces by seeds and vegetatively. Daughter plants form on rhizomes forming dense beds of water hyacinth. In one study, two plants produced 1200 daughter plants in four months.
Individual plants break off of the mat and are dispersed by water currents.
As many as 5000 seeds can be produced by a single plant. Seeds are eaten and transported by water fowl. The seeds sink to the bottom and may remain viable for 15 years. Seedlings are common on mud banks exposed by low water levels. The best way to manage water hyacinth is to keep it from becoming established in Washington.