Love ’em or hate ’em, poinsettias are indisputably our number one holiday potted plant. This year, 70+ million poinsettias will be sold in the U.S. for more than 250 million dollars between Thanksgiving and Christmas, accounting for roughly 25 percent of the annual potted plant market.
Here in the Upstate, many gardeners know the plant’s common name honors Joel Poinsett, a Charleston native with a summer home in Greenville who served as the first United States Ambassador to Mexico.
Plants which arrived in the U.S. nearly 200 years ago were initially given the botanical name Euphorbia poinsettia by John Bartram of Philadelphia, but Euphorbia pulcherrima, meaning “the most beautiful euphorb,” was published first by German botanists, and thus adopted as the official name.
Euphoria is a large genus of plants with about 2,000 species and includes annuals and perennials as well as trees and shrubs. All have a milky sap and are further distinguished by a cyathium made of fused bracts which form a cup around tiny flowers at branch tips. Some, such as the poinsettia, have clusters of cyathia, plus additional bracts (a modified leaf) that provide color.
Last December, thanks to a program at the Poinsett Hotel by Dr. Jim Faust of Clemson University, I had the opportunity to see a wild poinsettia collected from southern Mexico and photographs of the plant growing in its native habitat, where it can reach 12 to 15-feet tall. In addition to its form as a gangly, single-stalk shrub, the wild plant is quite different from those we know today.
In the wild, the cyathia at the tip of the stalk form an open center and the colorful bracts, which turn bright red in reaction to shorter day length of the winter equinox, are narrow in shape and droop downwards, away from the branch tip.
Many stories claim that Joel Poinsett collected poinsettias from the wild, but Dr. Faust believes it’s more likely those sent to the U.S. were gathered from markets, and thus the product of hundreds of years of selection.
Even though early imported plants were more decorative than their wild cousins, it took years of extensive research and breeding to produce the modern poinsettia. In fact, the earliest plants sold for the holidays did not branch, but included 3 or 4 individual plants with their stalks folded and doubled up on themselves (“tromboned”) to make a shorter plant.
Competitiveness among breeders, particularly as the market for the holiday sales grew, eventually unlocked the secret to producing a branching poinsettia, as well as a compact cluster of cyathia for a tight center, and more attractive bracts, including a wider variety of colors such as pink and white. In recent years, variegated bracts have become popular, and now those with striped, dotted, blotched, marbled bracts have joined the more traditional. Dark red, however, still accounts for roughly 75 percent of sales.
Today’s breeding efforts are focusing on hardier and longer-lasting poinsettias, as well as those that can transcend the holiday image. The recently introduced ‘Autumn Leaves’, with golden and pinky-peach bracts, is targeted for early sales. And some new hybridized plants are being called euphorbias rather than poinsettias, in the hope they will become a staple for winter and not only the holiday season.