Pontederia — 7 species

Pontederia is a genus of aquatic and semi-aquatic perennials native to the Americas, spanning the violet-blue spikes of pickerelweed (Pontederia cordata) to the fast-spreading Common Water Hyacinth. Plants require full sun and permanently wet or submerged roots, making them excellent choices for pond margins and water gardens. The ASPCA lists water hyacinth (Eichhornia/Pontederia) as toxic to cats and dogs, while Pontederia cordata (pickerelweed) is generally considered non-toxic — toxicity varies across species, so verify each one before buying.