The terroir of marijuana: Does wine country have the best soil and climate for cannabis?

Erich Pearson (Photo by Steven Krause)

California wine country is rapidly becoming California cannabis country. Will the two intoxicating cash crops compete for prime vineyard land?

There is very little experience in answering this question because marijuana has never been legally cultivated for recreational use. It has been grown where it could be grown (like greenhouses), not where it could be best grown.

Plus, there is no UC Davis for marijuana. Perhaps there will soon be a university research program devoted to cultivating cannabis for pleasure, but right now there's not even a word like "viticulture" ("cannaculture" doesn't have the same ring.)

I want to say this up front: I am licensed to ill in the great state of California, and I inhale. I have spoken to business writers who are covering the burgeoning marijuana industry but disavow any use of the product. I enjoy marijuana, as I enjoy wine, and that will inform my own (burgeoning?) coverage. Do you want to read wine stories from somebody who doesn't swallow?

I wanted to answer several questions about the terroir of marijuana. It took me some time to find someone to speak on the record. Erich Pearson is CEO of Sparc, a cannabis dispensary in San Francisco. You will see him quoted many places because Pearson is willing to be the face of an industry that has been in the shadows.

Sparc has a lease on a 400-acre farm in Glen Ellen, one of the warmer spots in Sonoma County, where the plan is to grow biodynamically. Here's an edited version of our conversation about the terroir of marijuana.

The Gray Report: What was your farm before?
Pearson: This was an old turkey farm. 40,000 turkeys at one point roamed these 400 acres. Their eggs were harvested and sold to make hatchlings. Currently it's about 2 acres of organic tomatoes. It's about 15 acres of free range organic beef cattle. And it's about 300 acres of free range chickens. Most of those vegetables and chickens go directly to a farmers' market. That is not us. That is our co-tenants. But we need livestock to grow biodynamically. We don't want the chickens in the marijuana fields during the year. We will allow the animals into the field and the cover crops in the winter.

TGR: What's the soil like?



Pearson: It's very heavy soil. It's heavy in clay. It may be good for grapes, but it's not great for cannabis. Cannabis doesn't like it too wet and it likes well-draining soils. So some of the soil right now is coming by truck from Oregon. It's mostly peat-moss based, but we don't know where that peat is coming from.

TGR: Why peat moss?
Pearson: It's a lighter substrate. Cannabis likes well-aerated soils. I can mix in the peat moss, but it's not going to be biodynamic. It's not going to be local input. We need to build in the cow manure. We need to compost a lot of stuff off the property to get the nitrogen level up suitable for cannabis.
We have an experiment that we're doing. We've taken a piece of land where the soil profile changes dramatically over about 200 square yards. We're making test plots. We understand what the soil's doing, and what happens with the soil as it goes deeper. We're growing clones in each plot and we're going to see what happens with those clones. Everything else is the same. The lighting and the climate are exactly the same. We're going to take some samples and see how it differs. That's terroir, right?

TGR: Yep, that's terroir. Are you dry farming?
Pearson: No. We're not dry farming. But we're certainly using less water with seed plants than with clone plants. Everything is going to be slightly different with seeds.
Mother Nature plants a taproot in cannabis. It sends a root down deep to get water. We feel that there's going to be a different product from a plant that has a taproot from one that does not (as in a greenhouse).

TGR: Sonoma County is going big into the marijuana business. Is the terroir there good for marijuana, or is it just that the political climate is welcoming?
Pearson: The easy one to answer is that it's legally welcome. Northern California is known for its marijuana. We have a large population that's going to understand the trade very well. We started this farm in February. I've got a lot of really passionate people who have grown marijuana. Because of that, we start off ahead of the game in northern California.
As far as the environment is concerned, it's hard to tell. The summers are dry in California. Cannabis does not like moisture when it's growing and when it flowers. The dry weather is important. Particularly where we are, the moisture that comes through the Petaluma Gap, that moisture is great for Pinot Noir. But the moisture is problematic for cannabis. Where we are on Sonoma Mountain, the mountain blocks the fog. This particular spot in Glen Ellen is dry, which is really beneficial. It's also hot, which can be a positive in spring but a negative in summer. Heat does vaporize terpenes. But I'll take hot weather over wet weather any day.

TGR: So Cabernet country is better for cannabis than Pinot Noir country.
Pearson: There's six acres of organic Cab on our farm.

TGR: A big question about terroir is assessing its impact on quality. I know how wineries judge quality: by the flavor of the wine, by alcohol percentage historically, by critics' scores more recently. How will cannabis growers judge quality?
Pearson: We'll send them to a lab. We always test our medicine. We test for THC content and CBD content and terpenes. Limonene is a terpene that's very common in citrus. You can taste that in the cannabis. Myrcene is a terpene that makes people tired. Higher myrcene profiles (in cannabis) make people sleepy. If test plot A measures higher in a particular terpene, consistently across different plants, we can say, up here, we're going to get more lemony cannabis, or more piney.

TGR: So it's not necessarily better if it gets more THC?
Pearson: No, certainly not. With the modernization of the cannabis consumer, there is a move toward processed cannabis. Five years ago, cannabis was never looked at as a commodity. People didn't ask how much THC can I get. If you talk to the people who do extractions, they can take the THC from different batches at different strengths and isolate them and reconstitute them into a product and make them the same. There is a shift in what consumers want: highly engineered products in cannabis that make them feel a certain way.
However, there's also a craft movement. People want the whole plant. They like the effect that's created by consuming all the different chemicals at once.

TGR: Wow, you are describing exactly a conflict in the wine industry between large consistent brands and small idiosyncratic single-vineyard wines.
Pearson: Cannabis is going to commoditize. The big boys are going to grow it in the central (San Joaquin) valley in big warehouses. {Editor's note: Also like wine!} There's a difference between growing mass amounts of cannabis and growing it biodynamically.

TGR: What is that difference?
Pearson: What is it in wine?

TGR: Well, I like a good western Sonoma Coast Pinot Noir, from the real Sonoma Coast, because of its complexity and unpredictability.
Pearson: Tasting flavor from smoke is different from tasting product from taste buds. Cannabis has not yet evolved as an artisanal product. This is the first time we're growing in soil. We've yet to see what the difference is between cannabis grown in soil and hydroponics.
Certainly you can compare something grown in hydroponics and something grown outdoor. It's much smoother outdoor. It doesn't have that bite on the nose. You can tell when something is not organic and has been pumped full of chemicals.

TGR: You're trying to grow biodynamically, but historically growers have used fertilizers and pesticides and whatever else they needed, right?
Pearson: I think the industry got a bad rap as a whole as trespass groves (people who grew on national park land, etc.). A lot of those people weren't medical marijuana growers. They don't represent the larger community of people. Many of my friends I've known for years, it's all organic, they take a lot of pride in what they do. The media drove these stories about trespass groves for many many years. That is all a result of prohibition.

TGR: What are your biggest environmental challenges in trying to grow organically?
Pearson: The biggest threat is botrytis, which is exactly the greatest threat to grapes. Gray mold, which we call bud rot. It's common in the fall when you get moisture followed by heat. It's the last thing grape farmers want, and it's the last thing we want.
And then insects. We have supermites. We have bugs that have evolved to withstand all the different things people used on them. It has been an unregulated industry. It's like overusing antibiotics. We have these mites that have evolved to resist the pesticides.
We have aphids that live down on the roots. They eat the tissue of the leaves, causing the plant to be stressed out. Its fuel source is getting damaged. The leaf of a cannabis plant is pretty soft compared to grapevines. Having an insectery, having honeybees, having vegetables -- biodiversity is crucial to biodynamics.

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