From which country and which time period did poinsettias spread worldwide?

Answer 1

From Mexico poinsettias (Euphorbia pulcherrima) were introduced into the United States of America in the 19th century, and from the United States poinsettias spread worldwide in the 20th century.

Specifically, poinsettias are native to southwestern Mexico. Despite European settlement of the Americas from the 15th century onwards, poinsettias remained unknown outside their native range. But in the 19th century Joel Roberts Poinsett (March 2, 1774 - December 12, 1851) changed all that during the course of his diplomatic career as Special Envoy of 1822-1823 and as first U.S. Minister of 1825-1830 in Mexico. Poinsett became the first person known to introduce poinsettias north of the U.S.-Mexico border.

In the 20th century, the Ecke family of Magdeburg, Germany immigrated to the U.S. They settled in the area of Hollywood, California and started up a successful cut-flower business. They decided to specialize in growing, promoting and selling poinsettias. From their California ranch poinsettias became known and were sold worldwide in the 20th century.