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Common Name: Water Hyacinth
Individual flowering plant
Photograph by: Tonynirappathu
Eichhornia crassipes is a perennial plant that can grow up to 0.25 metres tall.
It is harvested from the wild for local use as a food.
Tropics. Naturalized in central and southern Portugal[
]. Moist and boggy areas at elevations of 200 - 1500 metres in Nepal[
Prefers growing in a sunny but cool pool[
]. Water Hyacinth is reported to tolerate an annual precipitation of 82 to 270cm, an annual temperature range of 21.1 to 27.2°C and an estimated pH in the range of 5.0 to 7.5[
]. The leaves are killed by frost, and plants cannot tolerate water temperatures in excess of 34°C[
This species is not very cold-hardy, tolerating temperatures down to about 0°c[
]. It requires greenhouse protection over winter in Britain[
]. Plants can be grown outdoors in the warmer parts of the year and then be potted up in moist compost during long spells of cold weather[
A very invasive weed of water courses in the tropics[
], causing great environmental problems in many areas where it has become naturalized. Subsistence farmers in Bangladesh face disaster when rafts of water hyacinth weighing up to 300 tonnes per hectare float over their rice paddies. As the floods recede, the weeds remain on the germinating rice, thus killing it[
]. Engineers have estimated that the Panama Canal would be impassable within three years without continuous aquatic weed control measures[
Azotobacter chroococcum, a Nitrogen-fixing bacteria, may be concentrated around the bases of the petioles but doesn't fix Nitrogen unless the plant is suffering extreme Nitrogen-deficiency[
Young leaves and petioles - cooked[
]. Virtually tasteless[
]. Said to be used as a carotene-rich table vegetable in Formosa. Javanese sometimes cook and eat the green parts and inflorescence[
Flower spikes - cooked[
Seeds can tolerate submersion or desiccation for 15 years and still germinate[
]. Scarification, but not light, may be required for germination[