Consumers Beware: Some Landscape Plants Can Harm Environment

August 15, 1996

GAINESVILLE—Shopping at the nursery for something pretty and unusual to add to your home’s landscaping?

Be careful what you buy, University of Florida scientists warn. Some non-native plants sold as landscape plants are actually invasive species that can have a negative environmental impact well beyond your yard.

“We all want newer and better plants for our homes, but most people just don’t see plants as problems. The truth is, some plants are invasive and can escape and invade other areas, causing environmental damage to lakes, parks, forests, range land, preserves and agricultural areas,” said Donn Shilling, a professor of agronomy at UF’s Institute of Food and Agricultural Sciences.

“Tens of millions of dollars are spent each year to manage invasive plants, so the industry and consumers need to be better educated so they’ll know what they are selling, buying and planting,” he said.

A recent UF study of retail nurseries in Texas, Louisiana and Florida showed that many nurseries generally don’t label plants as native or non-native. The survey also showed that consumers knew very little about plants that have the potential to be harmful.

“One in three plants in nurseries is a native, the other two are exotic. People tend to select exotic plants because that is what they know and what is available in nurseries,” said Hallie Dozier, a doctoral student in the UF/IFAS forest resources and conservation department who conducted the study. “But it’s also really important to remember that only a small number of these exotics are invasive.”

During her survey, Dozier found coral ardisia, air potato, common lantana, Chinese tallow, heavenly bamboo, Chinese privet, and Japanese honeysuckle sold in nurseries. She also found an ornamental variety of cogongrass, which is known to revert to the invasive form of cogongrass. All of these ornamental varieties are thought to be invasive and are listed as such by ecological or environmental agencies. Still, Dozier said, any homeowner or landscaper can buy them.

To help get everyone on the same page, UF/IFAS has formed the Task Force on Invasive Plants. This group, comprised of scientists from several disciplines, is working in partnership with

landscapers, nurseries, botanical gardens, land and water resource managers and federal and state agencies to develop strategies for prevention and management, said Shilling, who serves as chairman.

“Our role is to find what information people need and what we can contribute to help provide safe and beneficial horticultural plants for the public,” Shilling said. “In Florida, we have over 750 non-native harmful plants and that list is growing every year. The first step is education.”

A good start also would be in changing people’s mindsets, he adds.

“Philosophically, people don’t view plants as pests; They see them as inherently good. But some people, in an ecological sense, can see where invasive species like melaleuca, kudzu, hydrilla and cogongrass are becoming a catastrophic problem,” Shilling said. “Florida has a unique character in its natural areas and people need to understand their role in preserving the natural balance.”