Some say tomoto and some say tomato. Some say poinsetta and some say poinsettia. In both cases, either pronunciation is acceptable.
This traditional holiday houseplant, a native of Mexico, is named for Joel Roberts Poinsett, the first United States Ambassador to Mexico (circa 1820). Poinsett was interested in botany, so he searched for new plant species from which he could take cuttings and bring them back to his greenhouse in South Carolina. You can guess his most important find.
Poinsettia is the plant’s common name. Its scientific name is Euphorbia pulcherrima, meaning “very beautiful.” John Bartram of Pennsylvania, the father of the American nursery industry, was the first to sell poinsettias under their botanical name. The Ecke family of southern California began growing and selling poinsettias in the early 1900s and is today the leading producer in the U.S.
Caring for poinsettias is easy. Getting them to rebloom is not. Keep your poinsettia warm (60º-70º) and sunny. Water only when the soil is dry. They like moist soil but not wet feet. Reducing the nighttime temperature to 55º-60º will extend their bloom time. Don’t fertilize when they are in bloom.
If you want your poinsettias to rebloom, they require 14 to 15 hours of total darkness from about October 1 until the bracts begin to turn color shortly after Thanksgiving. You have to keep them in total darkness from 5:00 PM until 8:00 AM. Any little exposure to light can prevent flowering. It has been suggested that you place a paper grocery bag (if you can find one) over the plant each night or that you put it in a light-tight closet. I’ve tried both methods to no avail. So, good luck.
Many gardeners ask if the poinsettia will grow outdoors. In our climate, you can put them outdoors only when there is no danger of frost.
As for the name, botanical purists may insist on calling them poinsettias, but most botanists won’t fault you if you say poinsetta. It is perfectly acceptable.