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Get Ready to Grow in a Greenhouse

November 8, 2016

Greenhouses are nothing new in growing; they’re not a new thing for cannabis, either. But as our industry strives for efficiency, sustainability and, of course, greater profit margins, greenhouses will become the new standard for cannabis farms.

Perhaps you’re already a grower working in a warehouse. Or maybe you’re a new or prospective grower who’s still deciding whether to move to a greenhouse or an outdoor grow.

From a cost perspective, grow locations break down like this: Warehouse > Greenhouse > Outdoor, with the warehouse being the most expensive and outdoor being the least. This assumes grows of comparable plant counts and identical media (soil, hydroponics, etc.). As with any business, labor will swallow up most of the costs, followed by maintenance resources (water, feed, etc.) and initial investment (equipment, licenses, etc.).

On the plus side

A greenhouse is an excellent middle ground for professional growers. For one, it nearly eliminates indoor electrical costs. Because there’s no need for rows upon rows of high-powered lights, there’s no need for massive amounts of power. Some growers see their electricity bills cut by 90 percent after switching to a greenhouse grow.

At the recent CannaGrow Expo in Denver, Jorge Cervantes gave a talk on greenhouses for cannabis. Cervantes is a long-time cultivator known for writing The Cannabis Grow Bible and The Cannabis Encyclopedia.

During his presentation, he showed the audience a spreadsheet breakdown of costs for warehouse vs. greenhouse vs. outdoor grows. Overall, there was a 33 percent reduction in total costs when switching from a warehouse to a greenhouse. Electrical costs were a large part of it, but so were costs for labor.

“The secret to growing indoors is to move outdoors, to a greenhouse,” Cervantes said. “You work less when growing in a greenhouse.”


The legendary Jorge Cervantes speaks to cultivators about growing in greenhouses at the recent CannaGrow Expo. (Photo: Randy Robinson)

A greenhouse’s reliance on sunlight offers other advantages. It provides full-spectrum light frequencies, translating to 30 percent more light efficiency over even the most advanced bulbs. And if you paint your greenhouse surfaces (floor, beddings, pots, etc.) with white reflective paint, you’ll reflect that sunlight from all angles, increasing its efficiency.

A greenhouse also offers more control over the grow environment. This control can be adjusted for your local climate, too. For example, you can install cement floors if you want to keep out bugs and moisture, or you can use the natural ground for your bedding if the environment is friendly.

In terms of grow cycles, most greenhouses aren’t restricted to seasons. Outdoor grows are always dependent on local climates and seasonal cycles (plant in spring, harvest in autumn). Warehouse grows can go year-round, but so can greenhouses, too.

Because greenhouses tend to exhibit excellent airflow, humidity modulation and temperature regulation, there’s a much lower chance of developing molds, mildews, fungi or bug infestations onsite. That translates to reduced use of pesticides and herbicides, which further translates into fewer expenses and greater profits.

One last piece of advice Cervantes gave his audience: “Make your own organic soil to cut down costs.” That may sound like extra work, but handcrafting nutritious soil for cannabis plants is fairly easy.

But are greenhouses legal?

In Colorado and Washington, the law requires that all commercial grows be secured and locked up, as well as hidden from public view. Modern greenhouses come with all sorts of security controls. It’s that second part (“hidden from public view”) that may create a legal gray area.

According to Lauren Davis, an attorney who specializes in Colorado’s cannabis laws, whether greenhouses are legal depends on the locality. The state’s Amendments 64 and 20 vaguely describe “enclosures” that cannot be easily accessible. Some municipalities will allow greenhouses as long as they are far away from people, while others may allow only greenhouses that can’t be seen from a public street.

In Washington state, the Liquor and Cannabis Board requires growers to apply for a special greenhouse permit. Only growers with that permit may operate out of a greenhouse.

In California, grow facilities are largely unregulated. Districts have begun crafting their own local regulations for grow operations, and some towns have given sweeping approvals of greenhouses across the board.

In other words, before embarking on a greenhouse grow, consult with an attorney who’s familiar with your local cannabis laws. You may be surprised how flexible your municipality is in regard to the “Green Rush.”

Where do I start?

After consulting an attorney, you’ll want to think about how to build your greenhouse. If there’s already one pre-built waiting for you, make sure it meets local regulations before starting a grow.

If you plan to build one yourself, there are a couple of options. If you know how to build a greenhouse and have a team assembled, you’ll need only initial investments in parts, labor and licensing. However, there are a few companies who specialize in building advanced, high-tech greenhouses. Most of them will not only customize your greenhouse to your specific needs, they’ll also provide consultation and maintenance services. That way, you can focus on growing the best buds possible while they take care of the other stuff.

By Randy Robinson
Cannabis Cultivation Today articles are for informational purposes only and should not be considered legal guidance or advice on grow practices. You should contact an attorney or a qualified cultivation consultant for specific compliance and cultivation advice.
© 2016 CAN Performance Group, LLC. All rights reserved.

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