Christmas plants like poinsettias and Christmas cactus help add to our holiday cheer, but where did they come from?

These beautiful plants have been decorating homes for the holidays since the 1800s.

Poinsettias (Euphorbia pulcherrima) were first introduced in 1825 by a man named Joel R. Poinsett, hence the name for the plant.

He was an American ambassador to Mexico. He noticed the plant with red bracts growing wild in the hills of southern Mexico and loved them so much he sent a few home to South Carolina and began propagating them and giving them to friends and botanical gardens around the Southeast.

A few years later, poinsettias were being sold at Christmastime in and around Philadelphia and New York.

It is hard to believe that once this lovely plant was used as a fever medicine. The Aztecs found practical uses for the milky white sap of the plant, today called latex. From its bracts, they extracted a purplish dye for use in their textiles and cosmetics.

More than 65 million poinsettias are sold in the U.S., making it the world's best-selling potted plant. They are available in an array of colors, from white to yellow to burgundy. Also, poinsettias come in a variegated or oak leaf foliage.

Christmas cactus is a succulent perennial that lacks spines and is native to the South American tropics of Brazil. These plants are forest cacti and are native to the mountainous rain forests.

Christmas cacti has been kept as a holiday houseplant since the 1800s. About 150 years ago, early breeders in England cross-pollinated the cacti.

It became popular in the 19th century Victorian England to give these plants as holiday gifts.

The Christmas cacti we see today in plant retailers and grocery stores is actually a hybrid of two different species of cacti.

This holiday favorite is called an epiphyte, which means it lives on other plants. Unlike a parasitic plant that obtains nutrients from its host, this cacti just uses their hosts as a place to live.

Both of these plants require cues from the environment to regulate the timed flowering. This function, called photoperiodism, occurs when the plants initiate flowering in response to relative lengths of daylight and darkness. In the winter, the days are shorter and nights longer; this is a very important indicator to the plants to stimulate them to start flowering.

In these species, it is actually the longer period of darkness that stimulates the growth - hence another connection to Christmas, too.

To preserve these plants after the holiday season, prune off the old growth after flowering and store in a cool place (50 to 60 degrees). Continue to water when soil is dry to the touch and they should set new buds once winter comes around next year.

Best wishes for a wonderful Christmas!

Wanda Cannon is a Master Gardener trained through the Hall County program and also serves as Master Gardener coordinator and horticulture assistant for the Hall County Extension office. Phone: 770-535-8293