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Put a Lid on Your Grow’s Smells

October 26, 2016

If you grow cannabis, you’re going to generate smells; that just comes with the territory. These fragrances pack quite a wallop in anyone’s nose, whether you cultivate the plant or not.

Although cannabis connoisseurs learn to love that skunky funk, not everyone finds the scent pleasing. We might disregard concerns regarding smell, but this is a serious issue. A few years ago, legislators in Denver tried to ban the smell of cannabis in residential area. About 70 miles south of Denver, Colorado Springs, Colo., officials cited local complaints about cannabis odor as a reason to ban new dispensaries from opening.

There are other reasons that you should be thinking about putting a lid on your grow smells. From a security standpoint, any building exuding the scent of cannabis is an easy target for thieves. And if your grow is in a community that isn’t terribly accepting of cannabis, it’s a good idea to cover up that scent. But how do you go about doing that?

Using carbon filters

Using filters to conceal the smell of cannabis is the most common and cost-effective method. Filters with carbon materials, such as charcoal, trap organic molecules in the air; in the case of cannabis, these molecules are the aromatic terpenes. Carbon filters are also known as “carbon scrubbers,” but there’s no actual scrubbing involved.

Carbon filters are excellent for filtering smells because they’re quiet, non-toxic, and come in a variety of sizes. Just make sure that the filters fit into your ventilation system, because they must be installed in some airway where the grow room’s air is either pushed or pulled through the filter.

To maximize your carbon filter efficiency, check the CFM (cubic feet per meter) ratings of both the filters and your grow room’s fans. CFM measures how much air the fan can move within a given amount of space. The carbon filter should match the CFM rating of your fans—or, better yet, select filters with a CFM just slightly higher than your fans’ CFM.

These filters work best in lower humidity, so try to keep the level at or below 70 percent, if possible. Also, because these filters trap smelly particles, they’ll get “full” at some point. Most filters last eight months to a year before they need replacing.

Companion planting

Companion planting is a technique where cannabis is grown alongside other plants or crops. This technique may not be suitable for your operation, depending on its size and location. Ideally, companion planting works best for outdoor grows, where you have the space for enough non-cannabis plants to overpower the scent of your crops.

You should select an abundance of plants that carry a potent smell. Lavender, lemongrass and other highly aromatic plants can mask or alter the smell coming from the cannabis. This isn’t guaranteed, and it requires experimentation, depending on what strains you’re growing.

On the other hand…

You’ll get a lot of advice on concealing smells, but carbon filters and companion plants are often your only viable options. Here’s a few methods you should steer clear of:

  • Ozone generators: Ozone is extremely toxic, especially if you’re pumping it indoors where you and your employees are breathing the air. Ozone can damage the lungs, and it’s bad for the environment. This method may even be banned in your area.
  • Air purifiers: These are good for your allergies, but they don’t work for cannabis odors, which are too potent even for industrial-grade purifiers.
  • Odor neutralizing agents: Also known as “smell gels,” most of these aren’t very effective in large-scale grows. Many neutralizers will taint the smell and flavor of your plants, giving them a chemical or perfume quality. However, some growers have found success with placing open ONA Gel containers just outside their grow room’s exhausts. These gels should never be placed inside the grow room.


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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