Scientific name

Thalia L.

Common names

water canna, powdery alligatorflag, Indian bayou, powdery thalia



Could be confused with

Monochoria, Pontederia

Native distribution


Species commonly cultivated

Thalia dealbata Fraser ex Roscoe (America)

T. geniculata L. (America)

Adventive distribution


Weed status

information not available


emergent broad leaved rosette plant

Brief description

Perennial. Emergent, tall. Stem narrow. Leaves alternate; petiole narrow, sheathed; leaf blade broad ovate-lanceolate, venation pinnate, lateral veins closely spaced and parallel; margin entire. Inflorescence an open, bracteate panicle. Flowers in sessile pairs, zygomorphic; sepals 3, subequal; petals 3, fused at base. Dispersal by seed.

Natural habitat

lakes, swamps, and rivers

Additional comments

A genus with seven species, with only a few aquatic. Thalia dealbata is the species most commonly cultivated for ponds. Thalia geniculata is slightly smaller than T. dealbata and has characteristic red stems basally.