This Red Stemmed Thalia, which is also known as Fire Flag, Alligator Flag, Hardy Water Canna, Giant Water Canna, Greater Thalia, or simply Thalia or Water Canna, is a large immersed plant in the arrowroot family Marantaceae, that grows in swamps and wet ditches from a thick rhizome. The broad bluish green canna-like leaves grow on reddish stalks and it bears purple-white flowers that grow above the plant and hang from zigzag stems.