There is a traditional plant for most seasons and holidays. Easter and Easter lilies go hand in hand. June and roses are linked. Halloween and pumpkins go together. Ditto for Thanksgiving and cranberries. And what would Christmas be without poinsettias?

Other plants play a part in all of the holiday seasons, of course, but in the case of poinsettias, they only seem to fit at Christmas. But do they ever fit. So much so, that 85 percent of all the plants sold during this season are poinsettias.

At one time, chrysanthemums were the fall flower fitting nowhere else because they bloom naturally in the fall when the days grow shorter and the nights lengthen. Then with the manipulation of light -- using shade to create the necessary long nights during the summer months or putting in lights to give longer days in mid-winter -- nurseries began to produce them year-round. People buy pot mums for all sorts of occasions, in spring, winter, summer and fall. Florists consider them a stock flower, always keeping some on hand.

A few years back, some growers decided to see if they couldn't do the same thing with poinsettias. They too can be forced by manipulating light. Valentines go with red and pink and poinsettias just might fill the bill. With new varieties always coming on the scene, that beauty could extend to other holidays. It all sounded so good on paper, but didn't reckon with the consumer. The concept of poinsettias as a part Christmas was so thoroughly entrenched that it became very clear that in the retail market there is nothing quite so dead in sales as a poinsettia after Christmas.

Nevertheless, growers across the country and around the state have been growing thousands of these attractive plants to grace tables, decorate homes and stores and to give as gifts for Christmas. Every state, including Alaska, has poinsettia growers. They are big business. In fact, about 90 percent of all the poinsettias that show up around the world are exported from the U.S.

The plants you may purchase this holiday were planted by growers late last summer. They grow for several weeks to get some size, and then sometime earlier in the fall, growers subject them to long nights, sheltering them from stray rays of light that might interrupt the dark period. This encourages them to color up for the right date.

The timing process is much easier now than it once was. Years ago, poinsettias put on their red and green color show and it lasted only a week or two before the bracts dropped off. If you missed the timetable, you were out of luck. Through breeding, newer varieties today may hold their color for months.

The petals of poinsettias are not petals at all. They are actually modified leaves (notice the shape) that surround the very tiny yellow flower in the center. Although the bracts of the original poinsettias were small and always red or white, breeding has produced a wide and delightful range of colors including pink, purple, yellow, and a wide array of blotched, flecked, mottled and spotted types. But red is still the favorite color of all.

Poinsettias have a long history on the American continents. The plants were important to the ancient Aztecs of Mexico. They used the sap of poinsettias to control fevers during the 14th through 16th centuries and the bracts were used to produce red dyes.

Poinsettias could not be grown at the high altitude of the land where Mexico City now lies, but that was where the royal city of the Aztec was. Montezuma, the last of the Aztec kings, ordered the flowers, called Cuetlaxochitl by his people, to be brought there by caravan so he could have a supply of them. Chile and Peru called the poinsettia the "Crown of the Andes."

Joel Roberts Poinsett, the first U.S. Ambassador to Mexico, was appointed by President John Quincy Adams in the 1820s, and brought the flowers to the U.S. A botanist, he was not the first to discover them. Botanist Juan Balme wrote about them in the 17th century.

Poinsett was a diplomat and eventually a congressman by profession, but was also fascinated with botany. Through his efforts, the American elm was introduced to Mexico. During his tenure there, he wandered the countryside looking for new plant species, and on one of his jaunts, he found a beautiful shrub with red flowers. He took cuttings from the plant and brought them home to his greenhouse in South Carolina. He sent some of the offspring of this plant to friends and from there it spread across the country and even overseas.

A German botanist, Wilenow, found one of these plants growing through a crack in his greenhouse and was dazzled by its color. He gave it the scientific name of Euphorbia pulcherrima meaning "very beautiful."

The poinsettia became more and more popular, but it had no common name. William Prescott, a historian and horticulturist, was asked to give Euphorbia pulcherrima a new and easier name. Prescott had just published a book, "The Conquest of Mexico" and in it he wrote about Poinsett's discovery. He named the plant, Poinsettia, to honor the American who introduced it to the world.

A family of southern California nurserymen, the Eckes, took an interest in the poinsettia. They began growing these plants outdoors in the 1900s for landscape plants and cut flowers. As the interest in the flowers expanded, so did the family business. They grew poinsettias in greenhouses and have since spent millions developing a palette of colorful varieties. Although Ecke didn't produce all of the new varieties, the company did develop most of them. There are about 100 different ones today. The Ecke company grows about 80 percent of the plants sold wholesale to growers who raise them to maturity for the retail trade.

Growing in their natural tropical environment, poinsettias are perennials and can reach up to 10 feet tall. They do tend to bloom in December when the days are shorter. We are accustomed to seeing these plants in festive pots or baskets and they are priced according to the number of blooms.

The sap that the Aztecs used for medicinal value is a milky white substance and for some people it can be a skin irritant. However, contrary to popular botanical legends, they are not poisonous. A study at Ohio State University showed that a 50-pound child would have to eat 500 bracts to get a very small tummy ache. Frankly, considering the flavor of the sap, that is highly unlikely.

When you purchase a poinsettia, you may want the freshest possible flowers. Remembering that these are the yellow structure or cythas growing in the center of the colored bracts, look for those that don't have pollen showing on them yet. The floral structure will complete its cycle and be shed long before the bracts drop off, so perhaps that search for freshness is incidental.

You can continue to grow and re-bloom poinsettias, but unless you love the novelty of tending these plants, it is far simpler to put it outside on a cold night and let it go when you are finished with it, and then purchase a new one next year. They are not particularly expensive and they do require a good deal of tending -- putting them in a dark place at night and uncovering during the day to get them to re-bloom. The re-bloomed bracts are typically not as big and showy as the ones that come from the florist because it is difficult to create the same environment in the home.