Water hyacinth are a free-floating tropical perennial plant . The dark green leave blades are circular to elliptical in shape attached to a spongy, inflated petiole.
Underneath the water is a thick, heavily branched, dark fibrous root system. The water hyacinth has striking light blue to violet flowers located on a terminal spike. Water hyacinth are a very aggressive plant and in our climate that can be a positive thing.
Water hyacinth can absorb a huge amount of excess nutrients from the water, resulting in clearer, healthier water. Their fast growth also helps to shade the pond, which helps in several ways. More shade equals less algae growth. The extra coverage give a refuge to fish being scared by predators and the huge floating roots give a hiding place to baby fry.
Water Hyacinth are tropical and should be tossed into the compost at the end of the season. They are next to impossible to over-winter so they are treated as a pond annual in our climate.
Water hyacinths should be controlled so they do not cover the entire pond. 50-70% coverage is ideal.