AMHERST, Mass. - Long a symbol of the holiday season, poinsettias are also important to the Massachusetts economy. While Bay State growers face stiff competition from Canada, more than 1 million poinsettias with a wholesale value of $4.6 million are raised by growers in Massachusetts every year. An increasing number of growers from the 200 greenhouse businesses across the state use training provided by UMass Extension to cultivate these popular holiday plants.
The UMass Extension Floriculture Program offers educational programs to greenhouse businesses to assist growers in practicing integrated pest management (IPM).The training encourages growers to use fewer pesticides in controlling whiteflies and other pests that commonly attack poinsettias. In general, IPM utilizes a variety of different strategies including mechanical, biological, and chemical controls to combat pests so growers use alternatives to pesticides whenever possible for control. In addition, with IPM, growers are encouraged to use environmentally safe pesticides at the most effective time during the pests’ life cycles. "IPM is a system for managing pests," says Tina Smith, extension specialist, "that takes the environment and people into account."
Since the greenhouse IPM program began in 1990, Smith reports, growers have reduced their use of pesticides on poinsettias by an average of 50 percent.
Poinsettia growers typically plant rooted cuttings in August for bloom in time for the holiday season, explains Smith. The plant’s blossoms are actually the yellow centers to groupings of colored leaves. These leaves – or bracts –come in various shades of reds, whites, pinks, variegated white and red, variegated white and pink, and even yellow.
Poinsettias, says Smith, are not dangerously poisonous, despite previous reports. She points to studies on the toxicity of the plants by researchers at Ohio State University that have proved that poinsettias are not harmful to human and animal health if parts of the plant are ingested. Smith adds, however, that poinsettias are not grown to be eaten, and as with all non-edible materials, they should be kept away from children and pets.
Though poinsettias are native to Mexico, several varieties are well-suited to the home environment, according to Smith. "To maintain poinsettias in the home," she says, "consumers should place the plant in a location receiving high light and temperature between 60 and 70 degrees. Keep poinsettias out of drafts and away from excess heat, and water the plants thoroughly when the soil is dry to the touch." With proper care, Smith says, poinsettias will remain colorful for several months.