“I feel like anybody who uses anything that is not organic, whether it’s food or smoke, or whatever, they are making a mistake,” said Dawson Julia, 45, another grower. “I feel like it’s a bad health choice.” (The fit-looking Mr. Julia offered this health tip: “I work 14 hours a day, and I smoke a lot of cannabis, so that’s my secret. No gyms allowed.”)

Getting the certification, however, was an arduous process in Maine.

Mr. Julia, who owns East Coast CBDs, which is housed in a warehouse in the small town of Unity, Me., is a longtime marijuana user. He said the state’s medical marijuana program, approved by citizens’ initiative in 2009, allowed him to turn his passion into a livelihood. “When it passed on the ballot, it was like a dream come true,” he said.

Mr. Julia sowed the seeds for the clean certification program in 2013. He was one of the first growers to approach the Maine Organic Farmers and Gardeners Association about it. The industry association has 11,000 members and a staff of 30, and it has been certifying Maine farms as organic since 1972.

“I called thinking I was just going to sign up for the program, you know, ‘I want to grow organic marijuana, where do I get the paperwork?’”

That is when he learned that the word “organic” is defined by the Department of Agriculture’s National Organic Program, which sets the standards for certification. Marijuana, still illegal under federal law, is not a crop the program recognizes (tobacco, however, is).

Image Harvested and dried marijuana buds await trimming. Credit... Tristan Spinski for The New York Times

Mr. Julia was undeterred. If the Maine association had no program for marijuana, he thought it could start one. If growers could not use the organic label, they would use another.