Propagation
Divide established clumps during late spring to early summer.

Botanic information
Leaf: The long sessile linear leaves are up to 20mm (¾in) wide with an obtuse apex and obvious parallel venation on both sides.

Flower: The tiny cyathiform female flowers are borne between opposite bracts with 3-perianth segments and have an inferior ovary. They are arranged on a long spiral peduncle that is flattened towards the top. The very small male flowers appear on a different plant during midsummer. 

Fruit: As the small fruit matures the spiral stems contracts dragging the fruit to the soil at the bottom of the pond. The small seeds are viable but the plant is normally reproduced vegetatively.