The poinsettia (/pɔɪnˈsɛt(i)ə/;[1][2][3] Euphorbia pulcherrima) is a commercially important flowering plant species of the diverse spurge family Euphorbiaceae.

It derives its common English name from Joel Roberts Poinsett, the first United States minister to Mexico, who is credited with introducing the plant to the US in the 1820s.

Every year in the United States, approximately 70 million poinsettias of many cultivated varieties are sold in a six-week period.

[7] It was known by the common name "poinsettia" as early as 1836,[8] derived from Joel Roberts Poinsett, a botanist and the first US Minister to Mexico.

[9] Possibly as early as 1826, Poinsett began sending poinsettias from Mexico back to his greenhouses in South Carolina.

They are grouped within the cyathia (small yellow structures found in the center of each leaf bunch, or false flowers).

Though Arnold later admitted that the story was hearsay and that poinsettias were not proven to be poisonous, the plant was thus thought deadly.

In 1970 the US Food and Drug Administration published a newsletter stating erroneously that "one poinsettia leaf can kill a child", and in 1980 they were prohibited from nursing homes in a county in North Carolina due to this supposed toxicity.

[4] A survey of more than 20,000 calls to the American Association of Poison Control Centers from 1985–1992 related to poinsettia exposure showed no fatalities.

There is a somewhat anomalous population of wild poinsettias in the northern part of the Mexican state of Guerrero and Oaxaca, which is much further inland in the hot and seasonally dry forests than the rest of the species' range.

[15] The tropical dry forests where wild poinsettias grow experience largely unregulated deforestation, resulting in habitat loss.

[11] From the 17th century, friars of the Franciscan Christian religious order in Mexico included the plants in their Christmas celebrations.

When Pepita laid her bouquet at the feet of the Christ Child, the weeds burst into bright red flowers.

[9] Cultivation in the US began when diplomat Joel Roberts Poinsett sent some of the plants back to his greenhouses in South Carolina in the 1820s.

Specific details about its spread from there are largely unverifiable, but it was exhibited at the Pennsylvania Horticultural Society's 1829 Philadelphia Flower Show by Colonel Robert Carr.

[8] Carr described it as "a new Euphorbia with bright scarlet bracts or floral leaves, presented to the Bartram Collection by Mr. Poinsett, United States Minister of Mexico.

[35] In Puerto Rico, where poinsettias are grown extensively in greenhouses, the industry is valued at $5 million annually.

[38] The discovery of the role phytoplasmas play in the growth of axillary buds is credited to Ing-Ming Lee of the USDA Agricultural Research Service.

[39] Albert Ecke emigrated from Germany to Los Angeles in 1900, opening a dairy and orchard in the Eagle Rock area.

He also appeared on television programs like The Tonight Show and Bob Hope's Christmas specials to promote the plants.

[32] Until the 1990s, the Ecke family, who had moved their operation to Encinitas, California, in 1923, had a virtual monopoly on poinsettias owing to a technique that made their plants much more attractive.