Poinsettia

The poinsettia, also identified as the Mexican flame leaf or Christmas star (Euphorbia pulcherrima), is a plant known for its striking red displays at Christmas time. It is often used as a floral Christmas decoration because of its festive colours.
The "flowers" are in fact large bunches of coloured leaves (modified bracts); the flowers themselves are in the center of each leaf bunch, but rather small and inconspicuous. Cultivars have been formed with orange, pale green, cream and marbled leaves. It is necessary that the plant receives no light at night between approximately October and Christmas. The slightest exposure to light during this critical period will often prevent "flowering".
Poinsettias are native to southern Mexico and Central America, where they may reach heights of sixteen feet. They are named after Joel Roberts Poinsett, the first United States ambassador to Mexico, who introduced the plant in the U.S. in 1825.