Follow the simple steps listed on the back of any of the popular wildflower seed mixes for sale, and voila! A thick carpet of kaleidoscopic blooms will grace your garden. Problem is, you probably just broke the law.
At least, that's what researchers with the University of Washington's Center for Urban Horticulture discovered when they grew the contents of 19 popular seed packages available in stores and mail-order catalogs. Every packet contained at least one species of plant listed as noxious or invasive in at least one state - a fineable misdemeanor in some regions - and several packets' lists of seed "ingredients" came up short, or the packets had no itemization whatsoever.
"It's not unusual," says Dr. Faith Campbell, an invasive weed expert with the American Lands Alliance. Invasive species are commonly - though not intentionally - sold in nurseries and seed packets across the country, she says. In fact, a federal law requires seed companies to list the total contents of each packet, as a preventive measure, though few do. "The University of Washington research was the first serious attempt to study the problem," Campbell says, "though people have been muttering about it for years."
Enforcement of the little-known invasive plant law is lax because there's little funding for either federal or local enforcement. "I can't recommend using any wildflower seed mixes," says Lorraine Brooks, who headed the project as part of an honor's thesis for her bachelor's degree. A safe approach to growing a wildflower garden, she suggests, is to buy each specific flower species separately after checking the list of banned plants in your state.
For information on the noxious or invasive plants listed in your state, check the USDA's Animal and Plants Health Inspection Service at www.aphis.usda.gov/ppq/permits/fnwsbycat-e.html.