Did You Know? The Truth About The Poinsettia

Courtesy of Mike Klopmeyer of Ball FloraPlant, West Chicago.

ST. PAUL, MN (December 1, 1998) -- Poinsettias, Christmas blooming masterpieces, are commonly found in North American homes during the holiday season. But did you know that poinsettias are tropical plants that originated in Central America and tropical Mexico? They grow as unbranched trees as high as 10 feet tall. Beloved by the Aztecs of Mexico as a symbol of purity; Joel Robert Poinsette, first United States Ambassador to Mexico and renowned botanist, introduced them into the United States in 1825.

How was a tropical tree transformed into the beautiful, branched plants we find in today's florist shops and stores? "Special seedling cultivars were first introduced in 1923," says Ing Ming Lee, USDA plant pathologist and member of the American Phytopathological Society. "Until recently we've never known what gave poinsettias their bushy, branched appearance. At first we thought a virus was involved, but the latest laboratory tests confirm the dwarf branching habit of the poinsettia is caused by a type of bacteria called a phytoplasma. Although highly unusual, its effects are spectacular in this plant."

Here are some additional poinsettia tips from the Plant Doctors this holiday season:

• Remember to keep your poinsettias in a sunny place for at least six hours each day, but don't let them touch cold windows. A chill will cause the poinsettia to drop its leaves.
  
• Keep the soil moist and water when the surface feels dry.
  
• After blooming is over, fertilizer will help keep the poinsettia healthy and promote new growth throughout the year.
  
• Contrary to popular belief, poinsettias are not poisonous. The Poisindex Information Service says that even at high doses of ingestion, no toxicity is indicated. However, keeping them away from pets or small children is still a good idea, since they will cause stomach aches if ingested.

Happy Holidays from the Plant Doctors at the American Phytopathological Society. For more details on this fascinating subject visit our December feature with photographs and links to additional sites of poinsettia interest at www.scisoc.org. The American Phytopathological Society (APS) is a professional scientific organization dedicated to the study and control of plant disease with 5,000 members worldwide.