Poinsettias

Poinsettias, Euphorbia pulcherrima, are in the spurge family. The actual flowers are the tiny yellow discs in the center of red modified leaves known as bracts. These bracts are sometimes mistaken as the petals of the flower. Poinsettias have a natural tendency to bloom during the Christmas season because they are short-day plants, which require long nights to produce their vibrant color. The colorful bracts attract insects to the small yellow flowers for pollination.

Poinsettias can fit into many holiday decorating themes. In colors ranging from creamy white or pink to the traditional bright red, some varieties have bracts with patterns in red and white, pink, and white, or even green and white. Some are bright orange. They are sometimes known as the lobster flower or the flame-leaf flower, due to the red color. Unusually-colored blue and purple poinsettias are often seen in stores or garden centers. They do not grow like this; to get these colors the white or cream-colored varieties are dyed or spray painted and sometimes sprinkled with glitter for a sparkling holiday effect. New color varieties include white, pink, burgundy, and marbled and speckled colors. There are more than 100 varieties of poinsettias available today.

History of the Poinsettia

Native to Mexico, the poinsettia naturally grows as large perennial scraggly shrub that can grow 10 to 15 feet tall. Because it grows so prolifically, it is also sometimes considered to be a weed.

The Aztecs cultivated the poinsettia in southern Mexico. In the Aztec language, Nahuatl, the name for poinsettia is cuetlaxochitl, which translates as the "mortal flower that perishes and withers like all that is pure." Poinsettias were used in Aztec midwinter celebrations representing purity and blood sacrifices. The plant was prized by Aztec kings. Montezuma, the last Aztec King, was so fond of cuetlaxochitl that caravans of the plants were brought to him in the region which is now Mexico City, because they could not be cultivated in its high altitude.

Today in Mexico, the poinsettia is displayed in celebration of the "Dia de la Virgen," December 12^th and is called "La Flor de la Nochebuena"--Flower of the Holy Night, or Christmas Eve.

Joel Roberts Poinsett a botanist, physician, and first United States Ambassador to Mexico under President James Monroe, brought the plant into the United States in 1828. He sent plant cuttings of the winter-blooming tree he had found in Southern Mexico to his home in Charleston, South Carolina. He also introduced the plant to the Bartram Botanical Garden in Philadelphia. Robert Buist, a Philadelphia nurseryman, saw potential in the new plant, so he named it after Poinsett. By the mid-1830s, the plant was widely known in the United States as the "Poincettia." December 12 is National Poinsettia Day which recognizes Poinsett's contribution to botany as well as the holiday season.

Poinsettias growing wild in Southern California as sprawling, weedy shrubs caught the attention of the Albert Ecke family in the early 1900's. Despite the plants' leggy appearance, the family saw potential in the red and green plant that bloomed around Christmas. They initially sold the poinsettia as a cut flower. However, horticulturalist Paul Ecke sought to turn the ordinary-looking poinsettia from cut flower to an attractive, full-branched potted plant. Perfecting a secret grafting technique combining two varieties which caused seedlings to branch, Ecke now grew a bushier more compact plant that competitors could not duplicate. This technique cemented the family's place as leader in the poinsettia-growing industry through much of the 20^th century.

Third generation Paul Ecke Jr. controlled the business in 1963 and popularized poinsettias so they would become associated as the flower of the Christmas season. He devised a unique marketing plan in which the Eckes ranch gave Poinsettia plants to the White House and various television shows, and to women's magazines as backdrops and décor featured throughout the holiday season. His plan was successful, and poinsettias became synonymous with American holiday celebrations.

Scientists became curious with the phenomenon of what made Eckes' plants so unique and started to investigate the family secret for growing such superior poinsettias. Around the mid-1990s, they found that a plant disease organism, known as phytoplasma, caused the unusual branching and shape of Ecke's poinsettias. The Eckes made use of grafting techniques to infect plants with the pathogen to encourage branching, and therefore to control the industry for decades.

Once the secret became known and competitors moved in, the advantage the Eckes once held was lessened. However, The Paul Ecke Ranch in California still grows over 70% of poinsettias purchased in the United States and accounts for approximately 50% of worldwide sales of poinsettias.

Choosing your Poinsettia

Choose plants with clean, healthy, dark green leaves. Avoid plants displaying pale green, yellow, or fallen leaves, however, note that cultivars with lighter-colored or mottled bracts may have lighter green foliage. If the plant has a paper or foil wrapper, pull it down to check that leaves at the base of the plant are healthy as well. Avoid plants with very dry or very wet soil and with wilted, damaged, or missing leaves. Observe the undersides of the leaves and leaf connections to the stem for insects and insect damage. Do not buy plants that have pests. Look for plants that are balanced, full, and attractive from all sides.

Poinsettias are very sensitive to cold temperatures and drafts. If temperatures are below 50°F or it is windy outside, put your plant inside a loose-fitting bag. When outside temperatures approach 35°F, be sure the plant is well covered or sleeved before transporting. Low temperatures, even for short periods, can damage leaves and bracts. Remove the protective or decorative sleeves promptly to prevent epinasty, a downward bending of the petioles, the thin stalks that attach the bracts to the stem.

Caring for your Poinsettia

Proper indoor care can help poinsettias maintain their striking appearance and increase their longevity beyond the holiday season.

Location and light:
Do not place plants in areas prone to drafts or temperature fluctuations such as near heat vents, fireplaces, appliances, doors, and cold windows, because leaf and flower drop may occur. Put them in an area with bright natural indirect light from the south, east, or west--at least six hours daily. Avoid direct sunlight or diffuse direct light with a window shade or sheer curtain because it may fade the color of the bracts.

Temperature:
Poinsettias prefer room temperatures between 55 and 65°F at night and 65 to 70°F during the day. Keep them away from cooler locations and avoid exposing them to temperatures below 50°F. They cannot tolerate frost or freezing temperatures.

Water:
Poinsettias require moderately moist soil. Check plants frequently and water well when the soil feels dry, however, take care to water before plants begin to wilt. Make sure to avoid overwatering. Avoid wetting the foliage, apply water until it runs out the drainage holes and do not let plants sit in water-filled saucers for more than five minutes to avoid causing root rot.

Fertilizing:
To maintain green foliage and promote new growth indoors after the holidays, apply a balanced all-purpose house plant fertilizer about once per month. Always follow the directions on the fertilizer label. Poinsettias do well in the home and often keep their color until March or April.

Pests:
Poinsettias can be susceptible to pests. Careful inspection before purchasing a plant is important for avoiding pests. Keeping your plant in an ideal location and frequent inspection will help you manage pest and disease problems

Care After the Holiday Season

When the holidays are over you must decide what to do with your poinsettia. If you decide that it served you well as a beautiful holiday plant, but you want to move on, simply put it outside and compost it.

Poinsettias can be saved for the following year but require some work to force a rebloom. Keep in mind that even if you manage to rebloom them, they may not be as full and vibrant as when you first bought them from the nursery. However, many people look forward to the challenge of forcing the bloom from their original poinsettia. If this is what you decide, with proper care, poinsettia bracts can be maintained until about March or April. Once they begin to drop, trim the plant back to about 8 inches high, leaving a few leaves and about six buds. For the first few weeks, the plant may resemble a bare stick. Keep the plant near a sunny window and continue to water regularly. By May, new growth will begin from nodes on the stem. Fertilize every two to three weeks with a well-balanced complete fertilizer such as 10-10-10.

For an unusual outdoor plant, Poinsettias can be moved outside in the spring when all danger of frost is past, and the night temperature remains above 50°F. Place the plant in partial to full shade and in early June, repot into a container about 2 to 4 inches larger than the original pot. Use a soil mix high in organic matter. Ensure that the new pot has good drainage. Poinsettias can also be planted directly in a garden bed that receives low or indirect light. To stimulate branching, pinch back the shoot tips or prune back the branches periodically. Stop pinching back after September 1 or flowers may not have enough time to develop for the holiday season. When night temperatures become cool, 55 to 60°F, bring the plant indoors to a sunny location and reduce fertilizer applications.

At this point, the poinsettia requires special care. Poinsettia is a short-day plant, which means it needs a long dark period each night to form its colorful bracts. Poinsettias set buds and produce flowers as the autumn nights lengthen, blooming naturally during November or December. The reduction in light is crucial because this prevents the plant from producing chlorophyll, the pigment that makes plants green and changes the bracts to their various colors, depending on the variety. Starting about October 1, your plant needs at least 14 hours of uninterrupted darkness each night at temperatures between 60 and 70°F. It can be put in a closet, in a dark room, or covered with a box or bag. During the day, put the poinsettia in bright sunshine. The poinsettia needs a long night and a short day. Continue to water and fertilize at a reduced rate. Keep this dark/light process going until about Thanksgiving at which point you can discontinue the process and just keep the plant in a direct light location that provides at least six hours of light daily.

Note that stray light of any kind--streetlights, table lamps, or just a small light leak can delay or prevent the reflowering process. Reblooming a poinsettia may sound intimidating, however, if the procedure is followed correctly, in early- to mid-December you should see color on the leaves and you should have a colorful poinsettia for Christmas. Some modern cultivars may even display color two weeks before Thanksgiving.

Enjoy your "new" poinsettia and be proud of your accomplishment! You can start the process all over again after the new year.

Written by Joan Banyas, Penn State Extension Master Gardener Luzerne County