MOORHEAD — As gardeners begin shopping for plants this spring, they may see some marked as safe for bees.

Some nurseries are offering plants that are free of an insecticide that experts have partly blamed for a die-off of bee populations in recent years.

Bachman’s is now reportedly growing plants at its Lakeville production center that are free of the neonicotinoid insecticide. While the insecticide is probably not the only cause of bee deaths, Bachman’s chief executive Dale Bachman calls it a precautionary measure.

He said he’d rather reduce the insecticide in his nursery and wait to see if science proves neonicotinoids are safe.

The issue is a hot topic in the gardening industry. As researchers and lawmakers seek ways to protect and restore bee populations, a national trade group called AmericanHort is supporting more research on the issue.

University of Minnesota entomology professor Marla Spivak said she hopes the Minnesota Legislature will pass a bill requiring that plants be labeled so consumers know which insecticide is used.

When used on seeds or in soil, neonicotinoid insecticides become part of the plant and kill pests. Growers like it because it reduces pesticide applications, but the insecticide gets into the pollen and nectar of flowering plants and can harm bees.

Joe Bischoff, regulatory and legislative affairs director with AmericanHort, said some of his group’s members are doing away with neonicotinoid insecticides. But he said he worries public opinion is getting ahead of science.

“Nothing is that black and white,” he said. “We really need to better understand the interaction and allow for that conversation and science to take us further before we have a sort of reactive response.”

Spivak said there are many unanswered questions about how bees and neonicotinoid insecticides interact in the environment.

“They’re certainly contributing, and we just don’t know enough about what the bees are actually picking up in the environment,” she said.