Botanical name: Stachytarpheta indica Family: Verbenaceae (Verbena family)
Indian Snakeweed is a terrestrial, annual or perennial, erect subshrub, up to 2 m tall. Taproot white or brown. Stem quadrangular, solid, glabrous or hairy. Stipules absent. Leaves simple, not lobed or divided, opposite, stalked, elliptic or ovate, more than 2 cm long/wide, usually airy on both sides, margin coarsely dentate, apex acute or obtuse, base obtuse our rounded, pinnately veined. Stalkless blue flowers appear in a slender terminal spike, petals 5, blue, with white throat. Fruit is a nut. This plant is similar to the Blue Porterweed (Stachytarpheta jamaicensis). Whether the two are same, is not clear.
The flower labeled Indian Snakeweed is ...