Species commonly cultivated
Pontederia cordata L. (eastern North America and Central America)
P. rotundifolia (L.) Castellanos (Central and South America)
Australia, Europe, Africa, western North America
not usually weedy
Perennial. Stems floating, creeping or ascending (mature plants usually emergent), stoloniferous or rhizomatous, roots produced at nodes. Leaves submerged, floating or emergent, alternate, in compact rosettes, petiolate or sessile; leaf blade linear to elliptic or ovate, venation parallel; base sagittate to cordate. Inflorescence an elongate or globose, prostrate or erect spike, subtended by 2 spathes; spathes dissimilar: upper scale-like, lower leaf-like. Tubular perianth of 6 tepals in 2 whorls of 3, tubular, 2-lipped, blue to purple; median inner lobe larger than rest, often with yellow fleck. Seeds with spiny ridges. Dispersal by seed or stem fragments.
swamps, rivers, lakes, and streams
Pontederia (including Reussia Endler) contains approximately 7 species, with P. cordata being most commonly available. Several varieties of P. cordata are cultivated.