Propagation
Sow fresh seed during spring in wet soils, and maintain a warm temperature.

Divide the rhizome during spring.

Botanic information
Leaf: The leathery textured leaves are cordate to almost circular (orbicular) with 2-basial lobes and float flat on the water surface. The margin is entire and the slender petiole is up to 1m (3ft) long. 

Flower: The stellate flowers have 5-spreading petals with membranous margins with a folded ridged down the centre and has alternating stamens that are fused to the corolla tube. They are arranged in an axillary umbel that consists of two or more blooms and are held above the foliage on a long scape during summer. 

Fruit: The small oblong capsule is inclosed by persistent sepals and contains numerous small rounded smooth seeds. The small seeds are viable but the plant is commonly reproduced vegetatively.