Many people who dream of a white Christmas also like to bring a little of the tropics into their homes, by decorating with poinsettias.

The irony is sun-loving, warm-weather preferring poinsettias can easily be damaged by the temperatures that accompany a white Christmas, said Rebecca Schnelle, state extension specialist for floriculture and greenhouse crops in the University of Kentucky College of Agriculture.

"If it is below freezing when you purchase your poinsettias, be sure to cover the plants when outdoors," she said. "Even brief exposure to sub-freezing temperatures can severely damage poinsettias."

Demand for the plant has grown steadily over the past decade. Ironically, that has resulted in fewer growers producing larger numbers of plants.

"Poinsettia is a high-input crop that commands a fairly low price, so profit margins are tight, and only the most efficient growers can profitably produce poinsettias," Schnelle said. "In the greenhouse world, that translates to large, highly automated operations."

To produce the perfect plant for home décor, growers have their hands full. Poinsettias are propagated from cuttings between mid-July and mid-September. Producers must schedule it perfectly so the plants are in bloom at the right time. They must also monitor and control the plant's height, since in the wild poinsettias aren't the small tabletop plants we recognize; they're large shrubs or small multi-trunked trees. The plants are also highly susceptible to insects and disease, and they require precise fertilization.

And when consumers get the plants home, they're still not maintenance free.

"Poinsettias, like all plants, need light and water," Schnelle said. "But don't use too much water. After you water them, be sure to let the soil dry thoroughly before watering again. Also try to select a location near a sunny window to maximize the time your poinsettias will stay beautiful."

Schnelle is currently working on finding ways to make poinsettias last longer for the consumer.

Consumer demand has resulted in a host of new shapes and colors aside from the traditional red. White, pink and burgundy poinsettias can easily be found these days, along with dyed and glittered versions. And as for the long-standing myth about poinsettias being toxic? Schnelle said that scientific research has shown the plants are not poisonous to people, dogs or cats, even if eaten in large quantities.

"While there's no danger," she said, "I still recommend keeping poinsettias and all indoor plants out of the reach of children and pets."