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Mass. marijuana has to be ultra-sterile. Just one problem: It’s a plant

Regulators will reconsider the state’s strict microbe standard

At Holistic Health Group in Middleborough, cofounder Colonel Boothe, left, and cultivation director Geoffrey Phillips displayed vacuum-sealed bags containing a portion of their outdoor-grown marijuana crop that failed the state's microbe test.Craig F. Walker/Globe Staff

At Holistic Health Group’s farm in Middleborough, dozens of vacuum-sealed bags full of marijuana flower — worth hundreds of thousands of dollars at retail — have been sitting in a secure vault for months, stuck in limbo.

The problem? The marijuana, which was grown outdoors last season, flunked the strict laboratory tests for microbes that all legal cannabis in Massachusetts must pass before sale.

The standards are intended to protect consumers from moldy or bacteria-contaminated flower. But farmers across Massachusetts have complained that the state’s unusually tight rules are based on flimsy science, discourage outdoor growing and other sustainable practices, add to the high cost of pot, and defy the simple fact that cannabis is a plant, one adapted to grow in soil rich with microorganisms.


“We put a lot of love and nurturing into those plants for two and a half months, only to hit a wall,” said Holistic Health Group cofounder Colonel Boothe. “It could be as simple as maybe our employees weren’t wearing gloves one day. Or it could be we did nothing wrong. The lines are arbitrarily drawn.”

Colorado, California, Oregon, and many other states with legal marijuana require testing only for a handful of specific pathogens, such as salmonella and aspergillus. Massachusetts, on the other hand, places a low limit on the total amount of bacteria and fungus in each batch of regulated cannabis, regardless of whether they are harmful or benign species.

Meanwhile, state agriculture officials have banned the use of nearly all pesticides and fungicides on legal marijuana, unlike other states that allow the application of certain natural compounds used on organic food.

Farmers say that would be akin to a doctor diagnosing a patient with strep throat after discovering any bacteria in her body, then refusing to prescribe antibiotics. They argue there is scant scientific evidence that properly cured cannabis — especially once smoked or vaporized — is a significant vector for infections, and say the ban on antimicrobial treatments leaves them with few tools to pass the unforgiving test.


State regulators say they are listening and considering revisions to the rule. Among the suggestions submitted to the Cannabis Control Commission: raising the microbe limits for outdoor-grown cannabis, allowing slight deviations above the current thresholds, or ditching total microbe counts in favor of tests for specific pathogens.

“We heard them,” said Shawn Collins, the commission’s executive director, referring to outdoor farmers. “We’re taking into account their considerations as unique operators . . . but also trying to balance that against the declaration to the public” that legal marijuana has been tested and deemed safe to consume.

Backed into a corner by the tight microbe limit and pesticide ban, most Massachusetts marijuana growers have essentially engineered nature out of the process.

At the indoor cultivation facilities that grew 97.7 percent of the flower available at Massachusetts dispensaries in 2020, rows of cannabis clones are typically planted under electricity-hogging lights in pots full of a sterile soil substitute such as “coco coir,” a wispy fibrous material made from coconut husks that can support plant roots, and fed synthetic nutrients. The air is heavily filtered; workers and visitors must don hair nets, lab coats, and shoe covers to avoid tracking in outside contaminants.

Several cultivators lamented that the $10 million to $20 million buildings feel more like the white-walled “clean rooms” where microchips are manufactured than farms.


“You don’t walk into a greenhouse and say, ‘Oh my God, this is the cleanest place in the world,’ ” said Reginald Stanfield, head horticulturalist at JustinCredible Cultivation in Cummington. “You expect soil to be there — living things. It’s overkill what we’re having to do right now. It feels like I’m manufacturing some secret government chemical. I wish I could keep it natural, but it’s an investment that needs to be repaid.”

The challenge is even steeper outdoors, where the state’s humid autumns promote microbial growth. Last season, nearly all the marijuana grown outdoors in Massachusetts failed its first microbe test, according to industry executives, while just 16.5 percent of all flower grown in the state (mostly indoors) flunked on the first try.

“The fall here is really tough with all the rain,” said Greg “Chemdog” Krzanowski, a longtime underground grower in Massachusetts who recently joined the legal business as the head of cultivation for Canna Provisions. “You have to find strains that finish [flowering] in September. Any later and you run into a lot of mold problems. You’ll be out there every day at 5 a.m. shaking all the dew and mist off.”

Cultivator Justin Bartlett tends to marijuana plants at the Canna Provisions growing facility in Sheffield.Craig F. Walker/Globe Staff

Growers whose harvests fail an initial microbe test can try various “remediation” techniques, ranging from hydrogen peroxide baths to radiation and ozone treatments, but those can be expensive and the resulting flower is often considered of lower quality.

Cultivators stuck with a “hot” crop can also use it as so-called biomass, low-grade marijuana that is ground and heavily processed into concentrates for use in edibles and vaporizers. But biomass in Massachusetts commands just $800 to $1,200 per pound at wholesale, while good-quality smokeable flower goes for $3,500 to $4,000. That’s not enough to justify much pampering of the plants, which is the dilemma facing Boothe, who paid several workers to carefully tend the Middleborough crop.


In this way, critics said, the strict limit makes outdoor cultivation financially risky, effectively freezing out equity applicants, craft cooperatives, the state’s 5,000-plus small family farms, and anyone else who can’t afford a multimillion-dollar indoor facility. It also drives up costs for marijuana consumers and patients, with companies charging more at the register to make back their big investments in climate-controlled warehouses, lab tests, remediation, and sanitation.

Holistic Health Group cofounder Colonel Boothe stood under the security cameras that monitor his company's outdoor cannabis farm in Middleborough.Craig F. Walker/Globe Staff

At EOS Farm in Pittsfield, founder Suehiko Ono is preparing to plant over two acres of outdoor-grown marijuana this summer, part of his mission to prove cannabis can serve as an ancillary cash crop for struggling family farms and that increasing the diversity of soil microbes actually makes marijuana safer.

Ono figures that despite the region’s limited growing season, outdoor-grown marijuana’s vastly lower upfront costs and artisanal marketability will make it a winner when the state cannabis sector matures or interstate trade is legalized and prices decline.

”A brand that’s grown in soil and sun by local farmers is a real story people can sink their teeth into and care about,” said Ono, who spearheaded the formal petition that prompted regulators to review the rules. “As opposed to, ‘I built another warehouse.’ ”


Commission officials said a decision is expected in the coming months, just in time, farmers hope, to decide whether it’s worth planting cannabis under the Massachusetts sun this season.

Dan Adams can be reached at Follow him on Twitter @Dan_Adams86.