About Pontederia vaginalis Burm.f.
Monochoria vaginalis (scientific name: Pontederia vaginalis Burm.f.) is a species of flowering plant in the water hyacinth family. It goes by several common names, including heartshape false pickerelweed and oval-leafed pondweed. It is native to a large portion of Asia and across many Pacific Islands, and it exists as an introduced species in other regions. It is often an invasive noxious weed, and is included on the United States Federal Noxious Weed List. As an aquatic plant, it becomes invasive in rice paddies and other water bodies. It is an annual or perennial herb that grows in water from a small rhizome, and it has quite variable morphology. Its shiny green leaves grow up to around 12 centimeters long and 10 centimeters wide, and are borne on rigid, hollow petioles. Its inflorescence holds 3 to 25 flowers that open underwater, all at around the same time. Each flower has six purple-blue tepals just over one centimeter long. The fruit is a capsule around one centimeter long that holds many tiny winged seeds. In culinary use, in northern Luzon in the Philippines, the plant is called hahalung, hakhaklung in Ilocano, or saksaklung in Kalinga; the whole young plant, excluding the roots, is eaten as a vegetable.
