sentences:  The temperature tolerance of the water hyacinth is the following; its minimum growth temperature is ; its optimum growth temperature is ; its maximum growth temperature is , and its pH tolerance is estimated at 5.0–7.5.Leaves are killed by frost and plants do not tolerate water temperatures > .Water hyacinths do not grow where the average salinity is greater than 15% that of sea water (around 5 g salt per kg).