Frog Bit

Hydrocharis morsus-ranae

Frogbit is a small, free-floating plant of ponds, lakes, and still or slow-flowing waterways. It looks like a mini water-lily with green, rounded, kidney-shaped leaves, and a three-petalled white flower with a yellow centre. The petals often look thin and crinkly, and can appear to be translucent in bright sunshine.  Female flowers are solitary but the male flowers grow in twos or threes.    

In the winter, this plant becomes dormant and over-winters as a bud buried in the mud at the bottom of the pond or lake. The buds rise again in the spring to form new plants.   

Frogbit provides a useful shelter for tadpoles, small fish and insect larvae such as dragonflies. It is thought to be declining due to the enrichment of waterbodies by nutrients (such as phosphates and nitrates) from agriculture and domestic runoff.  

Where and when to see them

  • This aquatic plant flowers in July and August, and can be seen floating in slow-flowing waterways such as canals, ponds, ditches and reens. 

  • The Gwent Levels and the lower reaches of the Monmouthshire & Brecon Canal are thought to be local strongholds for this species, but it is believed to be declining in other areas.

Take care near waterbodies!