Why is it a problem? Forms dense mats which completely cover the water surface leading to altered water chemistry and composition at the detriment of other organisms.
What does it look like? General description: Perennial, aquatic plant, free-floating or anchored in shallow water, usually 10-20cm high but up to 1m when growing in dense mats; roots of floating plants long and feathery. Leaves: Dark shiny green occurring in rosettes with swollen, bladder-like petioles growing above the surface of the water. Flowers: Pale violet or blue, in 8-10 flowered spikes, upper petal with a prominent dark blue, yellow-centred patch. Flowers from November-April. Fruit/Seeds: Produces capsules with very fine seed.
Does the plant have any uses? Used as a fishpond or water feature ornamental.
Plant me instead alternatives White water-lily (Nymphaea lotus), blue water-lily (Nymphaea nouchali), small yellow water-lily (Nymphoides thunbergiana)