Joel Robert Poinsett was the first U.S. ambassador to Mexico and probably expected to be remembered as an important statesman for the work he did. I don't recall ever studying about his work as an ambassador, but he is remembered for a plant he introduced to our country. Poinsett found these beautiful plants growing in Mexico and sent samples to botanical gardens in 1825. Cuttings from these plants eventually found their way into the commercial greenhouse trade.

Poinsettias, of course, pre-date the ambassador's visit to Mexico. They were cultivated by Central American Indians and used by the Aztec king, Montezuma. Like other tropical plants, they could not be grown in Mexico City because of the high altitude, but were imported for his enjoyment. Spanish priests used the bright-colored plants in nativity processions in the 17th century.Dr. David Hartly, research director for Ecke Poinsettias, of Encinitas, Calif., shared some information on poinsettias with me during his recent visit to Salt Lake City. Ecke Poinsettias propagates more poinsettias than any other grower in the world. Each year, plant breeders at that facility develop more than 10,000 different kinds of plants. Each plant is carefully grown from seed and evaluated to determine commercial possibilities. Unfortunately, the success rate is very low. In a good year, only one or two of the original 10,000 plants actually comes into the commercial market.

The breeding work has greatly expanded the size, shape and color of these plants. They are now available in all shades of red, pink, and even a creamy white color. Other variations include polka dots on the leaves. The most important development from the consumer standpoint is not the color but the lasting ability of the plants.

The plants are interesting because the part that we call the flower is actually not the flower at all. The true flower, the tiny yellow-green nubs or buttons, are in the center of the brightly colored leaves. The highly colored parts of the plant are actually leaves, or bracts. Newer varieties of poinsettias hold their leaves and color for several months. Older varieties often dropped leaves very quickly when removed from the greenhouse.

Newer varieties last well in a home or office with only minimal care.

The first step toward a long-lasting poinsettia is to find those with the true flowers still attached. The tiny little yellow-green nubs in the center of the red bracts should be present and with little or no pollen showing.

Select plants with dark green leaves. Plants with yellow or missing leaves indicate poor fertilization, poor lighting or possibly root diseases.

The second step is to protect the plant on the trip home. Exposure to freezing temperatures for even a short period of time will cause the leaves and bracts to turn brown and drop off.

Third, poinsettias benefit from plenty of light. They prefer a window or other well-lighted area. The flowers, however, should not touch cold window panes nor get too cold. Plants keep best between 60 degrees and 70 degrees Fahrenheit. Higher temperatures, particularly from dry heating systems, cause the colors to fade and the bracts to drop.

Fourth, water only when the soil is dry to the touch. Plants should not wilt, but it is important that they never sit in water. Add water in sufficient amounts to drain out at the bottom of the pot to keep salts from accumulating. If you plan to keep your flower, fertilize it every two to four weeks with a blooming plant fertilizer.

Poinsettias erroneously show up on almost every list of poisonous plants. While children should not be allowed to eat poinsettias, the main hazard is the white milky sap. The sap, common to all Euphorbias, will irritate the skin of sensitive people. If you come in contact with the sap, wash it off with soap and water. The Society of American Florists has spent many thousands of dollars testing the toxicity of poinsettias. You would have to eat bushels of poinsettia leaves to ever get enough to make you sick, so they are not likely to cause anyone problems.

Poinsettia flowers do not last well as a cut flower. The milky sap should be sealed with a match or hot water, but even under the best of circumstances, they only last a day or two when removed from the plant.

Poinsettias are short-day plants and need a long night in which to bloom. Few gardeners have the time and/or the patience to rebloom their plant. It's probably money well spent to buy a nice one and enjoy it for the holidays. Replace it next year as you would do with a Christmas tree. They won't rebloom unless you are willing to lock the plant in a dark closet each night. This tactic and other time-consuming maneuvers mean you probably won't enjoy the beautiful red color again.