Poinsettias

The bright red blossoms and attractive green leaves of the poinsettia plant have become almost as closely associated with Christmas as the holly plant and the evergreen conifer. Technically known as Euphorbia pulcherrima, the poinsettia is a native plant of Mexico, introduced to the U.S. in 1828 by the first American Ambassador to Mexico, Joel Roberts Poinsett. A botanist, Poinsett was fascinated by the plant’s botanical oddities as well as its striking appearance and seasonal bloom. In its native tropical habitat the poinsettia is a low-growing skimpy-looking bush. The brilliant red poinsettia blossoms (which can also be striated, pink white or pale green) are merely leaves lacking in chlorophyll. The actual flowers are the small yellow clusters slightly beneath and surrounded by the leaves.

The dramatic appearance of the poinsettia encouraged the Aztecs to value the poinsettia. They used the bracts (the technical name for the brightly colored, but not solidly green leaves) to make a dye, and as an anti-bacterial for dressing wounds. Montezuma, the last of the Aztec kings, had caravans of the Cuetlaxochitl plants brought to the area now known as Mexico City since the plants did not thrive at high altitudes. Towards the end of the sixteenth century in Mexico, folklore references to a variety of stories about a little girl from a family too poor to afford a gift for the local before the church’s altar. Miraculously, the legend says, the leaves turned into bright crimson blossoms. By the mid seventeenth century, Franciscan friars serving missions throughout Mexico began incorporating poinsettia into their Christmas festivals.

The Eckes had two secret techniques for poinsettia propagation. First, they grafted two varieties of poinsettia together, thus making it possible for the resulting seedlings to branch outwardly, rather than merely grow upward. Secondly, they knew that the colors of the bracts derive from photoperiodism. The bracts are initially  green, but then change to red (or pink or cream) but the bracts require darkness (12 hours at a time for at least five days in a row) to change color. On the other hand, once Poinsettias finish that process, the plants require abundant light during the day for the brightest color.

It is thanks to the Ecke family of Southern California that we are so very familiar with the poinsettia as a Christmas and holiday plant. In their native habitat, poinsettias can grow up to ten feet tall. Until the 1990s, when a university botanist figured out how they did it, the Eckes controlled the secret of propagating Poinsettias so that their poinsettias were were bushy, leafy and compact, instead of the usual spindly, vertical-growing shrubs.

It’s not terribly difficult to keep a poinsettia healthy and in “bloom” during the Christmas season, and even after. It’s even possible to have the same poinsettia plant bloom year after year, since they are perennials. During December and January, while the plant has crimson or other colored bracts, check the soil daily. If the soil is dry to the touch, then water the poinsettia until the water runs out of the drainage hole (but do not leave the plant sitting in water). I usually put the pot in the sink and use the sprayer to thoroughly soak the soil. Poinsettias need sun, so avoid a northern window in favor of one facing, south, east or even west. Avoid direct contact with the window’s cold surface. For year-round care, see this page. . And, in case you were wondering, no, the poinsettia is not poisonous though some people may have a contact allergy to the latex in the poinsettia’s sap, a characteristic of Euphorbia plants, including Crown of Thorns. Cats and dogs, however, should be kept away from Poinsettias.