This report from Forbes Magazine, published on 24 September 2026.
Key takeaways
- Legacy outdoor farms are outperforming expectations at major competitions, including this year’s California State Fair and the Emerald Cup
- Rising indoor costs — electricity, HVAC, real estate, compliance — are pushing cultivators and manufacturers toward sun grown and light-deprivation growing
- A cannabis geneticist says outdoor environments may unlock secondary-metabolite expression that indoor conditions simplify away
- Regions like Humboldt, Mendocino and the Sierra foothills could eventually claim the kind of “terroir” identity Napa has for wine
For much of the past decade, “indoor” has functioned as retail shorthand for quality in the cannabis industry. Dense colas, glossy trichomes, bag appeal engineered under high-intensity lighting — walk into almost any dispensary in the country and the priciest eighths are, more often than not, grown inside a warehouse.
A growing number of cultivators, processors, brand builders and scientists say that default has the agriculture backwards. Cannabis evolved under the sun, and the case for sun grown cannabis — grown outdoors or in greenhouses under natural light — has moved well past nostalgia for legacy hill farms. It’s now built on competition results, cultivation economics, consumer behavior and plant science.
Mark Greyshock has grown cannabis indoors, in greenhouses and outdoors for 30 years in California. His operation, Greenshock Farms, has collected more than 50 state awards and medals, including nine consecutive winning years at the Emerald Cup and five straight years of recognition at the California State Fair — culminating this year in the Golden Bear award for the state’s best sun grown flower.
Sun Grown Is Winning Where It’s Judged Most Strictly: In Competition
“I truly believe that sun grown represents the best possible flower one can find,” Greyshock says via email. Not every outdoor harvest reaches that bar, he’s quick to note, but in the hands of farmers who’ve spent their careers on it, sun grown flower can represent “some of the finest cannabis in the world” — a product of California’s diverse microclimates and terroir, paired with some of its best breeders.
Luna Stower, a certified ganjier who has worked across cannabis education, brand strategy and manufacturing for more than a decade, points to Greenshock’s Golden Bear win as part of a broader pattern: legacy outdoor farms continuing to take top honors at the Emerald Cup and other major competitions. “Those results are based on the quality and expression of the flower,” she says over an email exchange, “beyond just nostalgia for a style of cultivation.”
Consumers Don’t Dislike Sun Grown — They Haven’t Met It Yet
Scott Vasterling has lived in Humboldt County for more than 20 years and founded Humboldt Family Farms, a collaborative that brings small, family-run sun grown operations to market together. He doesn’t think California has a consumer-preference problem with outdoor cannabis. He thinks it has an exposure problem.
“Most consumers walk into a dispensary and see a wall of products organized by THC percentage, price and brand,” Vasterling says by email. “Nobody has really taken the time to say, ‘Here’s the farm. Here’s the person who grew this. Here’s why growing it under the sun in Humboldt actually matters.’ Once you start telling that story and letting people experience the product, you get a very different reaction.”
He points to this year’s Outside Lands festival as evidence: amid a crowded field of brands, Humboldt Family Farms’ Guava Tsu pre-roll became the festival’s highest-selling pre-roll. “Nobody walking in had to buy sun grown cannabis,” he says. “They tried it, they liked it, they told their friends. That’s a pretty good real-world test.”
The company’s model, he says, is essentially “the farmer’s market of cannabis” — letting consumers know where a product came from, and ideally who grew it, rather than reducing it to a THC number on a shelf label.
California’s Untapped “Napa Valley” Opportunity
Stower argues the industry has an economic opportunity it’s largely left on the table: building regional identity around cultivation the way the wine industry has. “Mendocino, Humboldt and the Sierra foothills deserve the kind of agricultural identity that wine gives Napa or Burgundy,” she says.
That identity, she adds, carries a cultural debt. Legacy sun grown farmers preserved cannabis genetics and cultivation knowledge through decades of prohibition, raids and criminalization — work the legal, regulated industry didn’t originate. “The regulated industry didn’t invent this plant,” Stower says. “It just inherited that work.”
Vasterling sees the same opportunity from a market-access angle. Humboldt is one of the most recognizable cannabis place-names in the world, he notes, yet consumers outside California have essentially never been able to legally buy Humboldt-grown flower. That could change as federal restrictions loosen. “Someday somebody in New York could walk into a store and choose cannabis from Humboldt the same way they choose a Napa wine or a Kentucky bourbon,” he says. “Humboldt has spent decades building this reputation. We just haven’t had the legal system that lets the rest of the world actually experience it yet.”
The Economics Nobody’s Pricing In
Jason Ambrosino runs a different part of the supply chain. As founder and CEO of Veterans Holdings, a New York cannabis company spanning manufacturing, processing and wholesale distribution, he thinks about sun grown less as a cultivation philosophy and more as a cost-structure problem.
“New York is an extraordinarily expensive place to grow cannabis,” Ambrosino says through email. “Electricity is expensive. Labor is expensive. HVAC is expensive. Compliance is expensive. Everything involved in creating an artificial environment inside a building costs money.” Indoor cultivation still has real value, he says, particularly for producing highly consistent premium flower — “but indoor cannot be the answer to everything.”
That matters, he argues, because demand has shifted beyond premium eighths toward affordable flower, pre-rolls, hash, rosin, vapes and edibles. “You cannot manufacture an inexpensive product indefinitely from an expensive agricultural input,” he says — a constraint he sees most clearly in solventless products, where “there is a mathematical limit to how inexpensive rosin can become when you’re washing extremely expensive indoor fresh frozen material.”
Ambrosino wants the industry to revive a distinction he thinks it forgot: tops, mids and lowers each have a different economic job. Premium colas become top-shelf flower; the plant’s consistent middle becomes value flower and pre-rolls; smaller material becomes hash, distillate or lower-cost pre-rolls. “That’s not an indictment of the plant,” he says. “That’s agricultural utilization.” He also points to a structural competitive issue: large indoor operators can spread fixed infrastructure costs across enormous canopies, while smaller cultivators carry the same HVAC, electrical and compliance burdens over far fewer square feet. New York’s licensing framework, notably, authorizes outdoor cultivation at significantly larger canopy sizes than its smaller indoor tiers — giving independent growers a path that doesn’t require out-building the biggest operators.
“The sun doesn’t send you an electric bill,” Ambrosino says — though he’s careful to note outdoor isn’t free. Land, irrigation, security, testing, labor and post-harvest handling still cost money.
He’s especially bullish on light-deprivation and mixed-light cultivation as an underused middle ground: it lets growers manage flowering cycles and harvest timing without assuming the full infrastructure cost of an indoor build. “I’ve seen very good light-dep cannabis that most consumers would have difficulty distinguishing from indoor based on appearance alone,” he says — though he cautions New York growers against chasing oversized outdoor colas purely for visual appeal, since dense, humid-season flower can become a magnet for botrytis. “Bigger isn’t automatically better.”
For Ambrosino, the more useful question isn’t indoor versus outdoor at all. It’s what genetics are being grown, what they cost to produce, and which finished product — flower, pre-roll, fresh-frozen, distillate — extracts the most value from each part of the plant. “That’s how a mature agricultural industry thinks,” he says.
What the Plant Science Actually Says
Anna Schwabe, a cannabis geneticist and plant scientist whose research focuses on genetic identity and phenotypic variation in Cannabis sativa, resists framing sun grown versus indoor as a quality contest at all. “I don’t think the question is whether sun grown or indoor cannabis is inherently better,” she says in an email interview. “I think it depends on what you’re trying to accomplish.”
Indoor cultivation, she notes, offers extraordinary control — light, temperature, humidity, irrigation and airflow can all be fine-tuned to optimize a specific genotype. But that control comes with a trade-off: simplification. Outdoor plants, by contrast, experience a constantly shifting environment — seasonal light changes, fluctuating temperature and humidity, variable wind, and interaction with soil microorganisms, insects and neighbouring plants. “Even vibration is an environmental input,” Schwabe says. “We know plants perceive and respond to their surroundings in ways that affect growth, development, defence and secondary metabolism, and there are almost certainly environmental interactions we still don’t fully understand.”
That added complexity makes outdoor cultivation harder to standardize — but it may also let a genotype express a broader or different chemical profile than it would indoors. “Genetics establishes the range of what a plant can potentially do,” she says. “Environment influences where within that range the plant actually ends up.” Her conclusion isn’t a case for replacing indoor with sun grown, but for recognizing they serve different goals: control and consistency favour indoor; the chance to observe chemistry that tightly managed conditions may suppress favors a closer look at sun grown. “I think we’ve only begun to understand what that difference actually means,” she says.
Stower frames the consumer-facing version of that same point: the body’s endocannabinoid system responds to a plant’s actual chemistry, not to whether it grew indoors or out. What matters, she says, is chemotype, purity, contaminant profile, maturity and post-harvest handling. But because cultivation environment can shape chemical expression, she argues that preserving diverse sun grown genetics and farming systems is still worth protecting — “more important,” she says, “than reducing cannabis to THC percentage and terp trends.”
The Energy and Sustainability Case
The environmental argument threads through nearly every voice in this story. Sun grown cultivation reduces dependence on high-intensity lighting, HVAC and dehumidification, Stower notes, and well-run outdoor farms can build in cover crops, compost, beneficial insects and water stewardship — treating the farm as an ecosystem rather than what she calls “a weed factory.” Greyshock makes the same point from the grower’s side: award-caliber sun grown flower is achievable “without the huge tax on the power grid that indoor cannabis consumes.” It’s the agricultural mirror of Ambrosino’s line from the manufacturing side — the sun doesn’t send anyone a utility bill, even if it doesn’t eliminate every other cost of running a farm.
The Bottom Line
The case for sun grown cannabis is that a mature cannabis economy needs multiple grades of agricultural input at multiple price points, that regions like Humboldt and Mendocino have a terroir story the industry has barely started to tell, and that outdoor cultivation’s added complexity may be less a limitation than an underexplored source of the plant’s chemical diversity.
As Ambrosino puts it, premium indoor can occupy the top of that pyramid — “but you cannot build the entire pyramid out of the most expensive material.” As legal barriers to interstate commerce fall and consumers get more exposure to where their cannabis actually comes from, sun grown regions may finally get the chance to build the kind of identity wine country spent a century earning.
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