Water hyacinth is a perennial plant belonging to the family Pontederiaceae, which is also known as the pickerelweed family. The plant may grow as an annual in temperate climates. Pickerelweed (Pontederia cordata) is an aquatic plant that is native to North America and has blue to purple flowers. A cultivated form is sold for aquatic gardens and could be an alternative for someone interested in water hyacinth.