Grow room sanitization is more important than you might think. Without properly sanitizing your grow room, your entire stash could end up in the trash.

To be clear, pests, mold and mildew can ruin plants. Though, there may be ways to stop an infestation or reduce its damage, the best practice is always a proactive preventative one. After all, the last thing you want is to get six weeks into flower only to discover spider mites or – GASP! – powdery mildew on your beautiful buds. Notably, it is dangerous to consume PM, but it’s also dangerous to consume some of the products growers use to remove it.

We always recommend using Trifecta Crop Control as a preventative for pests, mold and mildew and clean, healthy, NATURAL plants. When combined with maintaining proper grow room sanitization, you can avoid the (literal and figurative) headache when growing fine sinsemilla.

To help ensure your grow space is sanitary and your buds are safe, we’ve compiled this comprehensive guide to grow room sanitization. In it, we’ll discuss when to sanitize, why to sanitize, and how to sanitize your space, but first, let’s discuss the difference between sanitization and disinfection/sterilization.

Sanitizing Your Grow Room

Sanitization and Sterilization: What’s the Difference?

Cannabis plants thrive at temperatures between 70- and 80-degrees Fahrenheit. Unfortunately, so do molds, pathogens, fungus, and insects. Grow room sanitization is a crucial step to preventing infestations and reducing the risk of contaminated cannabis. But what does it mean to sanitize a space? It’s more than just cleaning (removing dirt and debris), though not as extreme as sterilization, which completely kills all living organisms.

According to the CDC, proper sanitization occurs when 99.9 percent of microorganisms die off within 30 seconds of application. Conversely, sterilization must kill 99.999 percent of microorganisms within five to ten minutes. Though a sanitized grow space is sufficient in most cases, you should still consider what the difference is between 99.9 percent efficacy and 99.999 percent. For example, if 99.9 percent of more than 100,000 commercial flights land safely, that means that more than 1,000 would not. However, if 99.999 landed safely, then only about ten would crash. Given that each surface contains millions of microorganisms, the more that remain after a good scrub, the higher the likelihood that a grow op could crash.

Notably, a sanitized grow room is generally sufficient in most situations. However, there may be times when your grow room requires more extensive sterilization. For example, should you experience a pest, mold or mildew infestation, you may opt for more thorough measures like disinfection or sterilization to help protect the next generation from a similar fate.

Sanitizing Solutions and Equipment

Before you can sanitize your grow space, you must gather your supplies. For example, you’ll likely want a vacuum with a HEPA filter, a garbage can for debris, towels, and a bucket to hold your cleaning solution.

Bleach to Sanitize Grow RoomNotably, there are many sanitizer solutions available online, but you can easily make your own using a mixture of two tablespoons of bleach to one quart of water. Note that you must make the solution strong enough to kill pathogens but diluted enough to protect your body, clothes, and equipment from its corrosive nature.

Hydrogen peroxide is another great sanitizing solution and is completely safe to use around plants. Some growers recommend using both (though certainly NOT at the same time!) in a two-step sanitizing process. One part of 30% hydrogen peroxide to one part of water is ideal.

Important: never mix cleaning solutions. Doing so could cause violent chemical reactions, including potential explosions.

You’ll also want a broom, a dustpan, a mop, and a bucket. Protective gear like gloves, goggles, and face masks are also important.

How to Sanitize a Grow Room

Now that you have your supplies, it’s time to sanitize your grow room. Begin by switching off all equipment except for exhaust fans, which will help rid the air of unwanted fumes. Next, remove anything you can from the grow space, including plants, pots, support systems, and lights if possible. Once you’ve cleared everything out, use a broom to sweep out the debris and use shop vac to remove dust from small spaces.

Prepare for Sanitization
Be sure to remove as much equipment as possible for thorough sanitization. PHOTO CREDIT THC Dispensaries Canada Inc.

If your last grow had a pest problem, you might use an insect bomb at this time to kill any remaining eggs and larvae. Don’t worry; you’ll remove any chemical residue during the next step in the grow room sanitization process. If you decide to bomb your grow area, remember to completely seal the area for at least 8-24 hours, and ventilate the area thoroughly before re-entering.

Next, use your bleach solution to wipe down all surfaces within the growing space. Remember to wipe down the walls, floor, and ceiling, plus any equipment within the growing space. This includes lights, trellises, pots, drip pans, and ventilation systems. Take extra care not to touch hot lights or saturate any electrical equipment with liquid. Use a three percent vinegar solution to clean reflective material then wipe again with distilled water to avoid calcium deposits which may dull the surface.

Cleaning Containers and Systems

If you re-use pots or grow using a hydro set-up, you’ll need to sanitize this equipment, as well. Notably, hydroponic growers tend to prefer using hydrogen peroxide because it is food- and plant-safe. Scrub all pots, containers, and drip trays with your hydrogen peroxide solution.

If you’re using a hydro system, carefully disassemble it to sterilize the entire system. Ensure that all areas are cleaned and rinsed of the solution before reassembling the hydroponics setup. You should also check all tubes and drip lines at this time and replace as necessary.

How to Clean Your Grow Room Vents

You should always clean your ventilation system when sanitizing a grow room. Remember to power down the system before cleaning, then wipe any dust off of its surface. Remove any pre-filter sleeves and anti-bug protections to wash, and inspect all seals for leaks, repairing with duct tape as necessary. If your carbon filter is at least 12-18 months old, replace it now, as well.

This is also a good time to inspect water filters, meters, electrical connections, and nutrient supplies and fix or replace them as necessary. After you’ve cleaned, sanitized, and dried all components, reassemble and test all connections to ensure the system works properly.

Sanitizing Your Grow Room

When and How to Sterilize a Growing Space

As mentioned, it is not always necessary to sterilize a space by completely eliminating pathogens. However, if you’ve experienced a pest, mold, or disease infestation, you may want to go the extra mile just to be sure. To be clear, sterilization is a much more detailed – and timely – process, which should result in the complete elimination of microorganisms within an area. Common sterilization methods include heat, filtration devices, and chemical cleaners, with chemical agents being the most popular.

To sterilize a growing space with chemical cleaners, simply soak hydroponic systems, growing media, containers, and cloning structures in a chemical bath (like the 1:2 hydrogen peroxide to water solution we discussed earlier). If your system is too large for a good soak, you can pump the sterile solution through the system instead. Just make sure to flush the chemical cleaner thoroughly from the system before using it again.

Vaporized Disinfectants Grow RoomsVaporized Disinfectants

Vaporized disinfectants use fogger machines to kill microbes across surfaces quickly. They are ideal for sanitizing large surfaces, plus all nooks, crannies, and seals. As such, vaporized disinfectants provide a much more thorough sanitizing solution than simply wiping surfaces with a disinfectant solution.

Hydrogen Peroxide

Notably, vaporized hydrogen peroxide (VHP) is one of the most common disinfectants because of its stability, affordability, and relatively low toxicity. When distributed through a fogger, tiny droplets of the disinfecting solution cover surfaces within seconds, killing all microbes and pathogens that it touches. However, it cannot penetrate dust, requiring a thorough wipe-down of all surfaces before application.

Chlorine Dioxide

Another vaporized disinfectant option is chlorine dioxide (not bleach) from companies like Gard’n Clean or ProKure. These products fight microbes very aggressively. They can also remove odors and stains such as those caused by mold and works well across many pH levels. However, it may not sufficiently kill all bacteria and fungus and may stain certain materials. Chlorine dioxide is also susceptible to contamination and degradation when exposed to light. Please check with your local board of health to ensure chlorine dioxide is allowed for use in your area.

Paracetic Acid

Unlike vaporized hydrogen peroxide, peracetic acid-based solutions do not require a follow up cleaning. They do require knowledge of your equipment materials as you cannot use them on copper or brass fittings. Additionally, they tend to have harsh odors and may cause nausea and skin irritation without the proper safety equipment. Always wear goggles, a face mask, long pants and sleeves, and gloves when using these products.

Using Heat to Sterilize a Grow Room

Another popular grow room sterilization solution involves heating the room (a.k.a. “baking it out”) to kill mildew spores and remove the room of excess moisture. To use this method, you must first remove everything from your grow room that isn’t tied down (e.g. your lights and ventilation system can stay).

Next, heat the room to temperatures ranging from 120 degrees to 140 degrees Fahrenheit for at least eight hours. By heating to these temps, you will be sure to destroy mold, mildew and any pests. If you do not follow the guidelines above by removing all equipment first, we strongly recommend checking with the manufacturers to ensure no damage will be incurred by high heat levels.

Follow the bake-out with at least 24 hours “cool down” time before beginning your next crop.

Many portable heater options can effectively sanitize a grow space, including products like the Portable Electric Salamander Heater from Grainger or Global Industrial’s Portable Electric Heater.

Best Practices for Grow Room Sanitization

Clean as You Go

Grow Room Sanitation
Pruners can be dipped or sprayed in disinfectant after cleaning for best practices. PHOTO CREDIT

Proper grow room sanitization does not end after the initial cleaning process. A healthy growing space requires a conscious effort to be sanitary throughout the entire growing process. Doing so protects plants from infestations and protects equipment from dust and dander that could clog the gears. Remember to wash hands and supplies before and after entering a growing space.

Keep plants and equipment organized and easy to maintain. Also, prune plants regularly (removing debris immediately) and clean any spills as they occur, as these are prime habitats for pests and pathogens. Finally, dust and maintain all equipment regularly, and keep your water source clean and fresh.

Use HEPA Filters

HEPA or high-efficiency particulate air filters remove particles from the air by forcing it through a fine screen. In doing, they can remove pet dander, dust mites, pollen, and tobacco smoke from the air with about 99 percent efficacy. TRUE HEPA filters take it a step farther by capturing around 99.97% of particulate in the air as little 0.3 microns large.

Use a vacuum with a HEPA filter and consider adding a HEPA filter to your growing area to help improve and maintain grow room sanitization. We recommend the Phoenix Guardian HEPA Air Scrubber from Jon-Don for its superior air quality remediation function.

Please note: never use vacuums or air purification systems with missing or faulty HEPA filters (including previously washed filters) to avoid kicking more particulate into the air and potentially contaminating equipment in the process.

Be Proactive

The best way to address an infestation is to avoid it altogether by combining the use of a preventative for pests, mold and mildew like Trifecta Crop Control with proper sanitization. Taking a proactive (rather than reactive) approach to grow room sanitization is easier, safer, and more affordable than the alternative. For example, it is much less hassle to sanitize a space before transferring plants into it than it is to deal with an infestation and the consequent loss in time and yields later. In other words, investing extra time into proactive grow room sanitization will pay for itself later. One step at a time; you got this!

Final Thoughts About Grow Room Sanitization

Growing your own cannabis is an exciting endeavor, but it requires a lot of work. Besides the standard watering, feeding, and pruning, you must also regularly clean and sanitize your growing space. The effort, though extensive, will save time, money, and hassle in the long run. After all, it’s always better to actively ward against pests and infestation than it is to fight them once they’re here.

If you’re experiencing issues with your plants, be sure to check out our plant problem identifier to figure them out quickly!

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