Large-flowered waterweed Egeria densa (aka Elodia densa)

Status Non-native, invasive
Best Time to See

A non-native invasive plant.

This submerged aquatic plant is very popular in freshwater aquaria. Plants are often discarded into the wild once they out-grow their tanks and can become established in warmer waters, such as industrially heated canals. It was first found in the wild in 1950 but not seen in flower until 2006.


Aquatic habitats.

What's the problem?

It seems that introduction as a result of dumping in the wild is increasing, and there is concern that if our climate warms even slightly, the plant could spread more quickly and out-compete native plants and clog up waterways and drainage systems. Large-flowered waterweed flowers only in warm water conditions. Conservationists in Cornwall are already having to deal with infestations of the plant in the wild.

Plantlife's position

This is a species that Plantlife believes should be listed on Schedule 9 of the Wildlife and Countryside Act in England and Wales.