The unusual highly divided flowers of Ragged Robin are fortunately quite distinctive for this attractive (if a bit dishevelled) flower. It is a native perennial of damper places, such as marshes, fens, woods and damp meadows, and also finds favour in gardens.

Flower: Little pink flowers, up to about 30 mm across, with 5 highly divided petals (not easy to recognise as such without close inspection)
Leaves: Narrow and lanceolate in opposite pairs
Habitat: Damp places - marshes, fens, woods and damp meadows
Height to about  1 m
Typically flowering: May - June