Wednesday, December 12, 2012

Poinsettia



The poinsettia (play /pɔɪnˈsɛti.ə/) (Euphorbia pulcherrima) is a culturally and commercially important plant species of the diverse spurge family that is indigenous to Mexico and Central America. It is particularly well known for its red and green foliage and is widely used in Christmas floral displays. It derives its common English name from Joel Roberts Poinsett, the first United States Minister to Mexico, who introduced the plant into the United States in 1825.

Description


Leaves, bracts & flowers at Jayanti in Buxa Tiger Reserve in Jalpaiguri district of West Bengal, India.

Euphorbia pulcherrima is a shrub or small tree, typically reaching a height of 0.6 to 4 m (2 to 16 ft). The plant bears dark green dentate leaves that measure 7 to 16 cm (3 to 6 inches) in length. The colored bracts—which are most often flaming red but can be orange, pale green, cream, pink, white or marbled—are often mistaken for flower petals because of their groupings and colors, but are actually leaves. The colors of the bracts are created through photoperiodism, meaning that they require darkness (12 hours at a time for at least 5 days in a row) to change color. At the same time, the plants require abundant light during the day for the brightest color.

The flowers of the poinsettia are unassuming and do not attract pollinators. They are grouped within small yellow structures found in the center of each leaf bunch, and are called cyathia.

The poinsettia is native to Mexico. It is found in the wild in deciduous tropical forest at moderate elevations from southern Sinaloa down the entire Pacific coast of Mexico to Chiapas and Guatemala. It is also found in the interior in the hot, seasonally dry forests of Guerrero, Oaxaca, and Chiapas. Reports of E. pulcherrima growing in the wild in Nicaragua and Costa Rica have yet to be confirmed by botanists.

There are over 100 cultivated varieties of poinsettia.

Religious and Other Traditional Associations

In Nahuatl, the language of the Aztecs, the plant is called Cuitlaxochitl (from cuitlatl, residue, and xochitl, flower) meaning "flower that grows in residues or soil." The Aztecs used the plant to produce red dye and as an antipyretic medication. Today it is known in Mexico and Guatemala as "Noche Buena", meaning Christmas Eve.

The plant's association with Christmas began in 16th century Mexico, where legend tells of a young girl who was too poor to provide a gift for the celebration of Jesus' birthday. The tale goes that the child was inspired by an angel to gather weeds from the roadside and place them in front of the church altar. Crimson "blossoms" sprouted from the weeds and became beautiful poinsettias. From the 17th century, Franciscan friars in Mexico included the plants in their Christmas celebrations. The star-shaped leaf pattern is said to symbolize the Star of Bethlehem, and the red color represents the blood sacrifice through the crucifixion of Jesus. In Spain it is known as "Flor de Pascua", meaning "Easter flower". In both Chile and Peru, the plant became known as "Crown of the Andes".

Poinsettias are popular Christmas decorations in homes, churches, offices, and elsewhere across North America. They are available in large numbers from grocery, drug, and hardware stores. In the United States, December 12 is National Poinsettia Day.

Creation of the American Poinsettia Industry

Albert Ecke emigrated from Germany to Los Angeles in 1900, opening a dairy and orchard in the Eagle Rock area. He became intrigued by the plant and sold them from street stands. His son, Paul Ecke, developed the grafting technique, but it was the third generation of Eckes, Paul Ecke, Jr., who was responsible for advancing the association between the plant and Christmas. Besides changing the market from mature plants shipped by rail to cuttings sent by air, he sent free plants to television stations for them to display on air from Thanksgiving to Christmas. He also appeared on television programs like The Tonight Show and Bob Hope's Christmas specials to promote the plants.

Until the 1990's, the Ecke family, who had moved their operation to Encinitas, California in 1923, had a virtual monopoly on poinsettias owing to a technological secret that made their plants much more attractive. The Ecke family's key to producing more desirable poinsettias was to create a fuller, more compact plant, by grafting two varieties of poinsettia together. A poinsettia left to grow on its own will naturally take an open, somewhat weedy look. The Eckes' technique made it possible to get every seedling to branch, resulting in a bushier plant.

In the 1990's, a university researcher discovered the method previously known only to the Eckes and published it, allowing competitors to flourish, particularly those using low-cost labor in Latin America. The Ecke family's business, now led by Paul Ecke III, decided to stop producing plants in the U.S., but as of 2008, they still serve about 70% of the domestic market and 50% of the worldwide market.

Cultivation


Poinsettia farm in Den Bommel, Nederland


A close-up photo of a Poinsettia (Euphorbia pulcherrima)

In areas outside its natural environment, it is commonly grown as an indoor plant where it prefers good morning sun, then shade in the hotter part of the day. However, it is widely grown and very popular in subtropical climates such as Australia.

The poinsettia has also been cultivated in Egypt since the 1860's. It was brought from Mexico during the Egyptian campaign. It is called "Bent El Consul", "the consul's daughter", referring to the U.S. ambassador Joel Poinsett.

With care, the poinsettia can be induced to reflower after the initial display when purchased. The red blooms should be pruned, and the plant moved outdoors after the last frost. It should be returned indoors in the Fall, before the first frost, to a room which is not lighted after sunset. The plant requires a period of uninterrupted long, dark nights for around two months in autumn in order to develop flowers. Incidental light at night during this time will hamper flower production. When watering it is important to allow the plant to drain out any excess water. Having a poinsettia sit in water can do harm to the plant as it prefers moist soil to direct water.

In order to produce extra axillary buds that are necessary for plants containing multiple flowers, a phytoplasma infection – whose symptoms include the proliferation of axillary buds – is used.

Diseases

Poinsettias are susceptible to several diseases, mostly fungal, but also bacterial and parasitic.

Toxicity Claims

In the United States and perhaps elsewhere, there is a common misconception that the poinsettia is highly toxic. This misconception was spread by a 1919 urban legend of a two-year-old child dying after consuming a poinsettia leaf.

While the sap and latex of many plants of the spurge genus are indeed toxic, the poinsettia's toxicity is relatively mild. Its latex can cause an allergic reaction in sensitive individuals. It is also mildly irritating to the skin or stomach and may sometimes cause diarrhea and vomiting if eaten. Sap introduced into the human eye may cause temporary blindness. An American Journal of Emergency Medicine study of 22,793 cases reported to the American Association of Poison Control Centers showed no fatalities, and furthermore that a strong majority of poinsettia exposures are accidental, involve children, and usually do not result in any type of medical treatment. POISINDEX, a major source for poison control centers, says it would take 500 bracts for a 50-pound child to eat an amount found to be toxic in experiments. An Ohio State University study showed no problems even with extremely large doses.

Links

The Wild Poinsettia Page: Images of Euphorbia pulcherrima in the wild in Mexico

USDA PLANTS Database, Symbol EUPU9, E. pulcherrima Willd. ex Klotzsch

Poinsettia FAQ.

Source: Wikipedia