Ludwigia sedioides, commonly known as mosaic flower and false loosestrife, is a herbaceous perennial plant of the family Onagraceae.

[2][3] Due to its rapid growth, efficient mode of reproduction, and aggressive nature, it has been identified as a potentially invasive plant in Sri Lanka.

It is found in standing pools of water with leaves floating on the surface, or growing in very swampy wet soils.

Leaves are diamond-shaped with toothed margins, radiate outwards to form mosaic-like rosettes.

The genus Ludwigia was named after German botanist and professor of medicine, Christian Gottlieb Ludwig.

The flowers are bright yellow, cup-shaped, solitary, produced in leaf axils from June to August in native habitats.