Do Grow Tents Keep In Smells? Tips to Control Odors


Grow tents are a convenient way to bring your garden indoors – no matter the season, your plants can grow perfectly in their own little cocoon of perpetual summer. However, your housemates and neighbors may not appreciate your indoor garden as much as you do, so keeping your hobby as odor-free as possible is probably one of your top priorities. 

Grow tents on their own do not keep in smells. While they may help contain and insulate smells, they do not block strong odors. The best method to absorb and neutralize smells created inside a grow tent is to ensure adequate ventilation and install a carbon filter.

Although a grow tent on its own may not be enough to contain smells completely, there are things you can do to keep things under control. Methods can range from simply masking smells to more high-tech exhaust systems. Let’s find out more about grow tents and how you can control odors associated with them.

Middle age grey-haired woman holding green plant pot at home smelling something stinky and disgusting, intolerable smell, holding
ID 239135983 © Aaron Amat | Dreamstime.com

Do Grow Tents Keep In Smells? 

A grow tent creates a controlled environment set up inside an enclosed space. It’s like a mini-world where you control everything, including the sun, rain, and plant life. While most good quality grow tents certainly offer excellent insulation, all the equipment needed to support and maintain the plants needs to be accessible from the outside – including yourself. 

Grow tents on their own cannot be relied on to keep smells inside. A good quality grow tent consists of a thick outer fabric that is heavy-duty enough to maintain even temperature and humidity levels inside the unit for the plants. Most grow tents also have a thick, reflective Mylar inner to optimize light, and to some extent, they do contain odors.

However, they are not entirely sealed. Odors can actively escape from the seams, zippers, and vents. As the fabric ages, the quality may deteriorate, or slight rips can occur, further diminishing the smell-proofness of the tent. 

For plants to grow successfully, they require good circulation. A grow tent without any ventilation system quickly gets a distinctive odor of chemicals, mold, and whatever is growing. The combination of heat and humidity inside your grow tent would soon become a humid, slimy mess if the air inside the tent became old, stagnant, and musty.

Your approach to keeping a grow tent smelling fresh depends on two factors:

  1. Do you need to control regular smells that may be caused by growing plants indoors in an enclosed space?
  2. Do you need to mask or eliminate the odor of a particular crop?  

When considering the smell in a grow tent, it is vital to view every aspect of the encapsulated space as an interlinked system. Any adjustment on one element will affect another. Increasing the airflow inside the tent will not only help to stabilize the temperature it will also keep the smell levels at bay. 

A concentrated smell is an indicator of inadequate venting and is far more likely to be noticeable outside your grow tent. Maintaining good ventilation inside a grow tent will also go a long way in reducing the risk of pests like mildew.

Learn more about what plants grow well in a grow tent in my article, What Can Grow In A Grow Tent?

8 Ways To Deal With Smells In Grow Tents

Limiting significant detectable odors from your grow tent is essential to keeping your system healthy. Depending on what you want to grow in your grow tent, controlling the smell may be as simple as ensuring adequate airflow, adding an oscillating fan, and cleaning regularly. 

Because grow tents are relatively small, warm, humid spaces, without proper attention, funky smells can build up pretty quickly, and some crops with pungent smells may need more focused odor control systems than others. While it is impossible to make a grow tent completely smell-proof, some effective tried-and-tested methods will go a long way in smell-proofing your tent. 

Carbon Filters To Absorb Odor

A carbon filter and exhaust fan are the most reliable methods to keep your grow tent free of smells. Most professional grow tents come with ventilation options. If keeping the setup smell-free is a top priority to you, besides investing in a good quality tent, installing a carbon filter is the best way to control odor. 

Carbon filters clean the air and absorb odors. This is the preferred air-cleaning method when growing strong-smelling plants inside a grow tent. I bought the VIVOSUN 4 Inch Air Carbon Filter for my grow tent.

VIVOSUN 4 Inch Air Carbon Filter Smellines Control with Australia Virgin...
  • Premium Australian Carbon: Made of Australian Virgin activated charcoal with high...
  • Excellent Odor Control: The porous activated carbon helps eliminate some of the most...
  • Detachable Pre-Filter Cloth: Equipped with a pre-filter cloth that blocks 99% of the particles...

Inline Fans to Increase Air Flow

Inline fans control the amount of air that enters and leaves your grow tent via ducting. The fans’ setup can allow air to enter passively or actively. If you choose the passive method, which is usually adequate on most grow tents, all you need is to ensure that the exhaust fan continuously removes hot and humid air from your setup. 

Active inline fan setups have two fans. One actively moves air into the grow tent, while the other works as the exhaust fan.

Most grow tents have inline fans installed in the roof of the tent. These allow the tent to be connected to a duct. There are usually two components – a fan that pushes air into an intake filter and an exhaust filter. Fitting the inline exhaust fan with an air cleaning carbon filter is the best way to keep your grow room’s smell in check. I picked up the iPower GLFANXINLINELITE4 4 Inch 195 CFM Inline Duct Ventilation Fan to go with the Vivosun Carbon Filter.

Maintain Negative Pressure

Having a larger exhaust fan than the inlet fan will ensure that any fumes created inside your grow tent are more likely to be sucked out rather than seeping through seams or vents into the outside room. However, be careful not to overdo things and put too much strain on your equipment or cause it to overheat and malfunction. 

To successfully use the negative pressure method to control smells, aim to take in 20% less air than is being expelled. 

Add An Oscillating Fan

Keeping the air in your grow tents smelling fresh isn’t just about removing and replacing air from the space. Keeping it circulating will make the stems of your plants stronger as the action mimics the movement of air outdoors. 

The other reason why adding an oscillating fan to your grow tent is helpful is that keeping the air circulating prevents harmful spores from settling on surfaces. A moldy interior can quickly make a tent smell stale and musty. 

Depending on the size of your tent, having one or even two small oscillating fans will keep the air moving. This will increase the chance of mold and mildew spores moving towards the inline fans and out of your tent – away from your precious plants.

For my smallish grow room, I used these rechargeable USB fans. They are usually marketed as stroller fans but work perfectly for a grow tent.

FRIZCOL Stroller Fan - Built-in 10000mAh Battery Operated Fan(Use for...
  • 【Upgraded - Long Battery Life】- Built-in 10000mAh large capacity battery, can be used for...
  • 【Upgraded - Flexible Tripod】- In 2022, we made an upgrade, the tripod is made of safe and...
  • 【Baby Friendly】- ①Soft wind: Switch between 3 wind speeds with one click, the breeze can...

Smell Absorbing Gel

One easy and cost-effective method to reduce the smell in your grow room is to use an odor-absorbing gel. The use of gels is not as effective as a carbon filter, and they work by neutralizing odors rather than absorbing them like the carbon filters. 

The gels are recommended for use outside the tent to neutralize regular smells associated with grow tents, rather than trying to mask the scent of any particular flowering plants. One of the most popular brands for grow tent setups is Ona Gel

Be Vigilant About Heat And Humidity

Grow tents often have a distinctive smell, but correctly managing the temperature and humidity of the environment will go a long way to controlling the production of smells before they even become a problem. Plants covered in mold or rotting are far more likely to cause unpleasant odors, and these conditions are often the result of being too hot or damp in the enclosure.

If you think you have too much humidity consider getting a dehumidifier. Check out my article Where To Place A Dehumidifier in a Grow Room for more details.

Clean Your Grow Tent Thoroughly After Each Grow Cycle

Besides eliminating any possible pathogens or bacteria, regularly spring cleaning the interior of your grow tent will make it smell fresh and revitalized for the next crop. So rather than harvesting and starting new plants immediately, spend some time wiping down the interior canvas with disinfectant.

 Starting with a fresh environment is always an excellent way to keep things smelling neutral, especially if you don’t need to hide the smell entirely and just want to make it more pleasant. If you don’t have a special grow tent cleaner handy, a 3% hydrogen peroxide or bleach will work. Open the entire tent up and wipe everything. Pay special attention to the vents and change the filters if needed. 

Check The Position Of Your Grow Tent

Sometimes a simple solution can be most effective. If you only have a slight problem with noticeable odors outside your tent, check if moving it will make a difference. Grow tents are brilliant for year-round gardening because you create a tiny microclimate inside the enclosure, so it doesn’t matter where a grow tent is situated so long as you have the necessary connections. It could even be inside a closet.

To keep mild odors emanating from your tent at bay, position the grow tent in a large, well-ventilated area with plenty of fresh air to diffuse any smells leaking out. It also helps to add a fan outside of the tent to keep the air moving, so odors don’t have a chance to build up and become overpowering. 

Grow Tent Features To Look For To Limit Smells 

If you are in the market to purchase a grow tent and odor control is one of your primary concerns, there are some features that you should take particular note of when choosing. While many indoor gardeners love the convenience of being able to grow no matter what the season, for others containing odors is a top priority. 

When looking through the vast selection of grow tents available, keep in mind what plants you will be cultivating, where it will be situated, and if you need to move it around frequently. If you need stealth for growing and don’t need loads of space, a grow box is a better option as it is a sealed unit and comes equipped with all the necessary ventilation built-in. 

However, grow boxes are often limited in size and, because they are all-in-one complete units, are far costlier than grow tents. Let’s take a look at how to choose a grow tent that will provide you with the space you need and be fully customizable for whatever crop you put inside while giving good options for odor control.

  • The thickness of the material – Thicker fabric will insulate the temperature and contain odors better. The best-known brand when it comes to insulation is Gorilla grow tents which offer grow tents at a thickness of 1680D. To get some idea of how thick that is, grow tents range in thickness starting from 200D!

Beginner grow tent owners should aim for an exterior fabric of at least 600D or above. The higher, the better, especially if the grow tent will need to be taken down and reconstructed frequently, which can damage the fabric.

  • Check the stitching, seams, and zippers – The thickness of the material won’t matter much if air can escape easily from poorly constructed seams or broken zippers. Check that seams are securely stitched and will be able to withstand the constant tension on the fabric. 
  • Decide how you plan to vent your grow tent – Ensure that the tent you get has the necessary openings and fittings conveniently situated to hook into your ducting system. 
  • Get a tent with viewing windows – If limiting smells is one of your top priorities, make sure that you can check your plants without having to open and close the grow tent frequently. 
  • Choose the correct sized grow tent – An cramped grow tent will produce more odor than a spacious, roomy one. If space is limited, pay careful attention to the ventilation you intend to install to ensure that the air inside the grow tent is constantly refreshed. 
  • Check that the fabric on the grow tent you select does not off-gas toxic vapors – when heated to high temperatures, PVC can release some pretty potent gases. Although there has been a lot of industry awareness around this issue, be aware that some smells inside your grow tent may not be from your plants or fertilizers at all, and it is worth checking the safety of the materials used. 

The grow tent I personally chose was the VIVOSUN 4×8 Grow Tent. It was a good compromise between quality and price. If you want to see my top picks for grow tents, check out my article, 5 Best Grow Tents.

Open Grow Tent

Final Thoughts

Grow tents do not keep in all smells as they are not entirely sealed units. If they are quality, well-constructed units, they will insulate odors and make them easier to manage. There are plenty of methods to reduce the smell associated with using a grow tent. The most effective strategy is to install a carbon filter in the inline vent. 

Diane Davies

Diane started out with a not so green thumb. After experimenting with different plants and methods of gardening, she was introduced to the Tower Garden and aeroponics. Now she loves to grow her own food easily on her balcony.

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