Water hyacinth

Description:

Spongy stalks, and oval broad leaves floating on the surface, and often forming floating islands that moves with current. It produces beautiful light blue flowers, some 15 of them on one stem.

Habitat:

Originally from South America, it thrives on shores and lakes in tropical region of Africa. Here, in urban setting, lose to shores in a swollen river in Niger river delta

Notes:

This is a very invasive species, and if not controlled, it can completely cover smaller lakes and shores of rivers.