See text Persicaria is a genus of herbaceous flowering plants in the knotweed family, Polygonaceae.

[5] The genus includes annual and perennial herbs with taproots or fibrous root systems, or with rhizomes or stolons.

The inflorescence may be a panicle or a spikelike or headlike arrangement of fascicles of flowers.

The flower is white, greenish, reddish, pink or purple, with the tepals partially fused together along the bases.

The fruit is an achene which can take a number of shapes, including a disc or a sphere.