What are neonicotinoids? Do I need to avoid them?
Insecticide applied to soil is trouble for bees, butterflies
Aimee Code takes special precautions when she receives a perennial plant as a gift. If she doesn’t know how it was grown, she’ll remove it from the potting soil and replant it. Then she’ll cut off the blossoms for several seasons to reduce the risk of exposing bees and other pollinators to neonicotinoid insecticides.
As the Pesticide Program director for the Xerces Society for Invertebrate Conservation, she’s all too aware of the toxic nature of this class of insecticides to bees, caterpillars, butterflies and other pollinators.
Neonicotinoids — sometimes referred to as “neonics” — are systemic insecticides used to treat insect pests. Neonics are applied to the soil instead of being sprayed on plants and can harm pollinators that visit flowers for pollen and nectar.
Code compares the effect of the two application methods as the difference between “drinking poison versus coming in contact with poison” for beneficial insects.
“Neonics have three strikes against them,” she explains. “They’re long-lived, highly toxic and they have an obvious exposure route to pollen and nectar.”
Gardeners who want to purchase neonic-free plants and plant materials need to ask questions about how plants were grown. Code suggests asking if the growing practices are organic or conventional. If conventional, ask if the plants have been treated with neonic insecticides.
“There are a lot of roadblocks to that,” she explains. “They may not know the answer or they may give the answer they think you want to hear.”
To avoid frustration, she suggests shopping at smaller nurseries, greenhouses and garden centers that grow their own plants. Other options are to shop at farmers markets that sell locally grown plants, shop at garden centers that know the practices of their wholesalers and growers, and trade untreated plants with neighbors.
While organically grown plants are safer for pollinators, some organic chemical treatments aren’t completely benign, Code adds.
She says it’s because people started asking about neonics at big box stores, like Home Depot and Lowe’s, that led to their commitment to phase out the use of the chemical insecticides on their flowering plants or to label plants with how they were treated.
Jason Shimmel, bedding plant manager at Sturtz and Copeland florist and garden center in Boulder, says it was pressure from consumers that led many local growers to pull neonics from use.
“This is our fourth season where we can guarantee the majority of our plants are neonic-free,” he says. “We use local growers in Fort Collins, Fort Lupton and Denver.”
Because other area garden centers source plants from the same growers, gardeners should be able to find neonic-free plants, he says.
Besides asking questions about how plants were treated, Shimmel advises gardeners to take the issue a step farther in their own gardens by using only organic pest controls and planting more native plants.
Native plants are a good choice because they help native bees, have fewer insect pest pressures and generally need fewer chemicals to treat them, he said.