By Sharon Omahen
University of Georgia
When the holidays are over and you pack away the decorations, don't pitch the poinsettia plant. If you're up for a challenge, this year's poinsettia could become a part of your holiday decorations next year.
Ron Oetting has several poinsettia plants in his greenhouse left over from past holidays. Oetting is a research entomologist with the University of Georgia College of Agricultural and Environmental Sciences.
Each year he is surrounded by a new crop of poinsettias he studies to solve insect problems growers face each year.
Saving can be a challenge
"I have new plants each year for research. But I also have a group of plants that I save from year to year," Oetting said. "You can save them from year to year at home, too. But it's a challenge. You just have to understand how a poinsettia works."
Once the Christmas presents have all been opened and holiday decorations are packed away, treat your poinsettia like any other houseplant. "You don't want to overwater or underwater a poinsettia plant," Oetting said.
During the spring and summer, a poinsettia is a green foliage plant. "When the weather turns warm, repot your poinsettia," he said. "You also need to decide whether you want your plant to be a bush or a tree."
Create a tree
If you fancy trees, he said, cut off all the plant's side shoots and leave a single runner that will grow upward. If a bush is more to your liking, pinch off the terminal shoot and the side shoots to make the plant branch more.
"Where you keep your poinsettia between New Year's and September doesn't make a whole lot of difference, as long as it gets light," Oetting said. "The tricky part comes after September.
"To flower, the plant needs the same amount of darkness Mother Nature provides," he said. "Somehow, you've got to keep that plant in the dark after the sun goes down, and it has to stay in the dark until the sun comes up. If there is any flash of light, you can forget it."
Once the plant begins turning the bright red it's known for, there's no turning back. "Once it starts turning, it's gonna go," Oetting said. "It's already set physiologically."
Oetting has seen this process work and fail.
Totally in the dark
"We saved some poinsettias in one greenhouse from the previous year and they were right on track," he said. "But the poinsettias in the greenhouse next door were doing poorly. We figured out why when we noticed the streetlight just outside the greenhouse door."
Oetting doesn't recommend trying to save your poinsettia plant unless you are up for a challenge and don't mind failure. "It's too easy to break the period of darkness," he said. "It's also a whole lot easier and cheaper to buy a new one each fall."
One unique characteristic of poinsettias is that its red "flowers" aren't actually flowers at all. The true flower of the plant is the small yellow flower in the center of the red color. The spectacular red, flower-like arrangements are the plant's bracts or leaves.
A tropical plant from Central America, the poinsettia is also known as the Christmas Star or the Mexican Flameleaf. It's named for its discoverer, J.R. Poinsett, the first U.S. ambassador to Mexico.
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)