Most legal cannabis in Illinois is grown without the sun, wind, rain or even, in some cases, soil.

But opportunities to grow cannabis outdoors in Illinois have been limited. State law, which requires that cannabis be grown in an “enclosed, locked facility,” allows greenhouses. But the law doesn’t address similar facilities like screen houses and hoop houses, which feature a metal frame with plastic sheets. The lack of clarity over the legality of such facilities has led to a tug-of-war between the cannabis industry and state regulators.

Two companies won state permission to grow cannabis in screened houses, but regulators later tried to revoke that permission. The companies went to court and won rulings that allowed them to keep growing outdoors.

A third company that is also one of the largest — Curaleaf — has filed a lawsuit seeking permission from the state to grow outdoors. Curaleaf, which already operates a greenhouse, wants to build a hoop house with 42,900 square feet of plant canopy space, an irrigation system and storage space. It also wants to build two additional hoop houses in the future.

Curaleaf Chairman and CEO Boris Jordan said in a statement that his company’s proposal complies with the state’s requirements for a secure facility.

“This roadblock represents yet another unfortunate example of state regulators obstructing the growth of the regulated cannabis industry,” Jordan said. “We believe that when regulators prevent licensed operators from expanding access to legal cannabis for patients and consumers, they are effectively pushing demand toward the illicit, unregulated market.”

The Illinois Department of Agriculture said in a statement that state cannabis laws require strict safety and security at growing facilities. And “as can be seen in other adult-use states, the subject of allowing outdoor cultivation is complex, and presents challenges of its own, including the need to mitigate the impacts of animal and insect life and the chemicals designed to protect against them.”

The regulatory agency also said it must weigh the potential impact on the production of hemp, which is derived from the same plant as cannabis but has less than 0.3% of THC, the component that gets users high.

Any significant change in the way outdoor cultivation is regulated could only be achieved through a change in state law or the administrative rulemaking process.

“This ensures that the entire industry, as well as advocacy groups and other impacted parties, all have an opportunity to participate in the discussion and that any resulting policy shift is applied to all licensees equally, at the same time, and in the same manner,” the Agriculture Department said in the statement.

There is precedent for growing cannabis legally outdoors in Illinois. Hemp is commonly grown in farm fields with no enclosures. Two cannabis companies — Green Thumb Industries (GTI) and Nature’s Grace and Wellness — went to court and won rulings that allow them to keep growing cannabis in screened houses. Some facilities also use translucent roofs on growing warehouses.

But when Curaleaf petitioned the state for permission to begin outdoor cultivation in hoop houses, state regulators told the company that solid walls and ceilings were required. Potential concerns included security and nearby farm pesticides drifting into the outdoor growing areas.

Like indoor growing facilities, outdoor cultivation sites must also be equipped with cameras and electronically locked security doors. Break-ins at Illinois cultivation centers are almost unheard of, but regulators often raise concerns about employee theft with cultivators.

In December 2024, Curaleaf asked the state for permission to build a hoop house, but the state never acted on the request. In response, regulators told Curaleaf they would be formally changing the rules to restrict outdoor grows, but have yet to do so. The company filed suit this year seeking a court order to proceed with the hoop house.

Other licensed business owners are watching the litigation with great interest, particularly craft growers and the more than 60 growers who have licenses but haven’t been able to open for business, mostly because of high costs and difficulty getting loans.

The Illinois Independent Craft Growers Association previously asked state regulators for permission to grow outdoors, but that request was denied.

“We said, “Flex here a little — let us grow outdoors for extraction only,” association President Scott Redman said. “The ability to grow outdoors would be a game changer for all these craft growers trying to get started.”

An indoor craft growing operation can cost $5 million to $10 million to build, Redman said, compared with as little as $250,000 for a hoop or screen house. Those businesses are under pressure from the state to open, because the state deadline for becoming operational was June 1, though business owners may apply for extensions.

Court records give an idea as to how Nature’s Grace won the right to grow outside.

In 2019, the state Department of Agriculture granted Nature’s Grace permission to use a screen house to grow cannabis with low levels of THC, the component that gets users high. The outdoor grow was to be used for extraction, which is a process of removing cannabinoids from the plant for infusion in edibles or concentrates, not for smoking the plant. The screen house was to cover approximately 43,500 square feet, surrounded by a 6-foot fence.

The state agency tried to rescind that permission in 2021, stating that the screen house was not enclosed and locked, with no floors, walls, or roof, was susceptible to infiltration by insects and animals, and was being used for high THC plants. But Nature’s Grace argued that such accusations were without foundation, and that any rule change would require going through a lengthy formal process with public hearings.

Nature’s Grace is a fifth-generation family-owned farm in Vermont, outside of Springfield, that raises cattle and grows corn outdoors. Its chief operating officer, Tim O’Hern, told the Tribune the screen house has been a success for growing plants for extraction.

“We like it quite a bit,” he said. “To use Mother Nature to grow the plant is probably the biggest advantage. It’s a lot lower electricity bill.”

Because a crop of cannabis requires about three months to grow, and needs at least 12 hours of darkness each night to flower, the Illinois climate only allows for one or two outdoor harvests a year.

O’Hern called for the state to ease up on some of its restrictions on cannabis, particularly in light of competition from largely unregulated hemp. Hemp can be grown outdoors, without the same requirements for security and testing, without the high taxes imposed on cannabis, and without even a mandated minimum age for customers.

“I don’t think we should be as scared of cannabis as maybe we were when legalization was passed,” he said.

GTI’s screen house, meant for cultivation of nonintoxicating CBD, has a 10-foot-high chain link fence around the perimeter, including the roof, with surveillance cameras and other security features on each corner.

The issue has much broader implications beyond any one grower. One new study by a University of California at Berkeley researcher found that indoor cannabis cultivation is a major emitter of greenhouse gases, with one warehouse producing 100 more times emissions than a similarly sized Walmart.

Outdoor growing could cut that output by 76%, a move that would support the Illinois Climate Action Plan, which has a goal of reducing carbon emissions to zero by 2050.

Other industry participants are watching the outcome of the case closely. Cole Preston, author of TheColeMemo.com website and podcast, who first reported on the outdoor grows, sees them not only as a boon for licensed growers, but says it should extend to home growers.

Currently, Illinois law limits home growing to medical cannabis patients, who may grow up to five plants indoors.

“I believe that as long as operators can produce a product that meets Illinois’ strict testing standards, there shouldn’t be an issue with how they grow — be it in an indoor cultivation center, a screen house, a hoop house, a green house, or another type of setup,” he said. Judging from the successful use of outdoor grows so far, he said, “There don’t appear to be any issues.”

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