| Although poinsettias are a multimillion-dollar business in the U.S. today, these fiery plants have ancient roots — they were first cultivated by the Aztecs hundreds of years ago. Native to Mexico and Guatemala, the poinsettia, known to the Aztecs as cuetlaxóchitl (kwet-la-sho-she), was used for medicinal purposes: The milky white sap was thought to increase milk production, dyes derived from the leaves (or bracts) were used in textiles, and some war rituals involved the plant. Poinsettias were also believed to hold magical properties, with one Native legend saying just the smell of a poinsettia could cause infection of the reproductive organs. So how exactly did these ancient Aztec plants become so closely associated with the winter holidays? Well, the first reason is biology. Poinsettias are typically (but not always) red and green — colors that have been associated with Christmas for millennia. The plant also often reaches full bloom in December. The second part of the equation arrived in the 17th century, when Spanish Franciscan friars used the plant to decorate altars and nativities. When the Vatican eventually used the plant for decoration, other Catholic churches throughout the world weren't far behind. In the early 20th century, farmers in California began mass-producing the plant in the U.S., and the venerable poinsettia has been a modern holiday must-have ever since. | 
