Poinsettias are the number one potted plant sold in the United States. This is amazing, given the fact that they sell mainly during the Christmas holiday season. They are colorful and fit the holiday perfectly.
We’ve finally refuted the old wives’ tale concerning the alleged claim that poinsettias are poisonous. The Society of American Florists and Ohio State University conducted a scientific investigation that conclusively disproved the charge that the poinsettia is harmful to human and animal health. It states that a 50-pound child would have to ingest over 500 bracts to surpass the experimental doses. There was no toxicity at this level.
This native of Mexico is a relative of other indoor plants, such as the Crown of Thorns and Croton, and annuals like the Chenille plant and Castor bean. Its showy bracts (modified leaves rather than flowers) come in a variety of colors and can last for months. The plant can be kept from year to year and can be brought back into color in the fall by giving the plant six to eight weeks of “short” days. The colorful bracts coincide with the plants’ flowers—small yellow buds found at the center of the bracts. The bracts may begin to fade as the flowers finish, so look for tighter buds when purchasing a poinsettia. New cultivars appear regularly, with currently more than 100 cultivars grown commercially.
Poinsettias should be protected from the cold when being transported from the store to your home, a trip that should be a short as possible. For the holidays, place your poinsettia in bright, indirect light. Allow the soil to dry moderately between waterings so that the roots don’t stand in water. If your poinsettia came wrapped in colorful foil, punch holes through the bottom of the foil to allow the pot to drain. Maintain temperatures between 70ºF and 75ºF during the day, with nights no lower than 60ºF—protect the plant from cold drafts.
When the leaves begin to fade, many growers recommend that the plant be cut back, and given a rest period of drier, cooler, and dimmer conditions. In spring, when new growth appears, place the plant in a very bright to direct sun location. Resume regular watering and fertilizing (apply a general houseplant formula according to label directions.) Some people prefer to keep their poinsettia in color through the winter and spring, so give the plant regular waterings and access to bright light.
Poinsettias benefit from summering outside in the morning sun or a dappled sun situation with regular water and fertilizer. For a bushier plant, pinch the plant back a couple of times over the summer until mid-August. Long nights induce poinsettia flowering, so beginning around October 1, start the “short-day” treatment described below.
The poinsettia is a long-night plant; that is, it flowers when the days are only 8-10 hours in length. As this plant would typically bloom in the spring, following its natural winter conditions, tricking the plant into an early winter means spring-blooming can take place for Christmas.
To initiate flowering, limit the plant to only 8 or 9 hours of good bright light each day for six to eight weeks, starting at the end of September. The other 15 to 16 hours should be dark (in a closet, under a box, etc.) Any interruption in the plant’s long night may prevent bud formation. Continue to water the plant as needed during this period, but do not fertilize. Once the bracts (top leaves) begin to darken or show color, discontinue the short-day treatment and the plant should continue to deepen in color.
TIP: To cut and use poinsettias in flower arrangements or on wreaths, plunge the cut end of the stem into boiling water for about a minute or singe the end with a match to stop the sap from running. Then place the stem in cool water for a day. Cut flowers can last a week or so.
The Christmas Poinsettia: The poinsettia is the most popular indoor Christmas plant. Its association with the Christmas season is because it blooms at this time of year in its native region. In the 1600s, Franciscan priests used the flowers in celebrating a nativity procession, Fiesta of Santa Pesebre. Mexican peoples regarded the poinsettia as symbolic of the Star of Bethlehem. There is a legend in Mexico that a poor girl, who could not afford to take flowers to the Nativity in her church, received instructions by an angel to pluck a weed and place it at the altar, where it miraculously transformed into a beautiful red poinsettia.
In the mid-1920s, the United States ambassador to Mexico, Joel Roberts Poinsett, sent some of the plants home. He shared some of his hothouse-grown poinsettias with botanical gardens, and eventually, his name became commonly used to identify this beautiful plant. Each year the poinsettia appeared as a short-lived, delicate flowering plant around Christmas time. Still, its popularity took off when hybridizers managed to give it more strength and a more extended flowering period in the 1960s.
Today, the poinsettia is not only the most popular Christmas plant, but it is the number one flowering potted plant in the United States, despite its short six-week season of availability. More than 65 million poinsettias are sold annually in the United States. Botanically Euphorbia pulcherrima, the poinsettia is not a toxic plant as it was long thought to be, although some people may be allergic to its sap.