Best Humidifier for Grow Room – Let Your Plants Breathe the Right Way

Recently I went for some flower shopping for my home. And, while choosing the plants I started talking to my florist. One thing led to another and soon we started talking about how plants are grown in dry conditions. And, the problems that can occur due to dry air. She even took me to see his shop's grow room and I immediately noticed a large humidifier. This gave me the idea of doing a guide for it.


Also, who better to interview than the experienced florist that simply knows what the plants really need. Luckily, she had the time to answer a few questions and help us out. Here's how the interview went and after that, you can see which humidifiers he recommended.


How Did I Chose It - I Asked an Expert

best humidifier for hard water - interview graphic image

As you've probably noticed from my last few buying guides, I have done interviews with various experts from different expertize areas.


This time, I interviewed a florist, Jannet Smith.


Here's what she had to say on the topic of the best humidifier for grow room.

Leona Maurer

Leona Maurer


Hello Jannet, welcome and thank you for taking the time to answer my questions.



Thank you, Leona, it is a pleasure and a great feeling to talk about the thing that I love doing.

Leona Maurer

Leona Maurer


Okay, let's start! First, I would like to ask you why do you actually need a humidifier in the grow room?




Well, maintaining proper air balance, moisture, and temperature in a grow room is essential for proper plant development.


Therefore, by controlling the humidity, you can control all 3 factors.


Also, there are many ways of doing so, but humidifiers are the best when it comes to hassle-free humidity control.


You just fill up the water tank, plug it in, set the humidity levels, and forget about it for a while.


Leona Maurer

Leona Maurer


Thank you. Can you please elaborate a bit on that?




As a matter of fact, I can. First, I would like to talk about how important it is to be able to control the humidity easily.


For example, you can put a stove in your grow room and simply boil the water and let the steam raise the humidity levels.


But, as you probably guessed, this is not a precise method and there's no guarantee it will be efficient enough.


Also, there's a lot of physical labor involved in this or other humidifying methods. And, that just wastes both your time and energy.


For those reasons, humidifiers are the best and most effective choice.


Leona Maurer

Leona Maurer


Okay, anything else you would like to add? Temperature?




Yes, temperature. When it comes to grow rooms, low or excessive temperatures in 99% bring problems and bad or no results.


You probably know that the air temperature is directly related to humidity levels.


Therefore, excessive or low temperatures mean unbalanced humidity levels and that only means problem with your plants.


Again, the right humidifier will take care of that problem for you easily.



Leona Maurer

Leona Maurer


What about the air purity? Should the air be clean for the plants?




Yes, great point. In order for the plants to thrive, the air should be free of dust, airborne impurities, and the harmful elements that can be found in the water.


So, knowing that humidifiers have filters, at least the good ones do, the mist that comes out of them will be clean. Meaning, the air purity level in your grow room will be high.


Thus, the plants will grow faster and better.


Leona Maurer

Leona Maurer


Okay, can we talk now about the humidity levels and which suit which plants the best?




Of course (laughing) this was the moment I was actually waiting for.


So, here's the breakdown:


  • 10% – 40% 

When the air humidity is between 10 and 40 percent, it is considered to be dry air. These are the conditions you encounter in a desert. Such conditions are great for Cacti and all arid plants. However, other plant species will not survive these conditions.

  • 40% – 60%

This humidity range is usually found during the summer in most homes and it is the easiest range to achieve with any humidifier. And, these are great conditions for the majority of plants that can be found in homes. But, when it comes to grow rooms, some plants will require additional misting in order to thrive.

  • 60% – 80%

For grow rooms, humidity levels between 60 and 80 percent are ideal for most of the plants. And, they will love the conditions. However, for achieving and maintaining such humidity levels, you will need a powerful humidifier.

  • 80% – 90%

If you want to grow tropical plants, these are the humidity levels that you have to reach. It is extremely hard to reach these levels. So, you if you plan on growing tropical plants, you have to consider getting a few powerful humidifiers.


Leona Maurer

Leona Maurer


Okay, we now know the proper humidity levels for plant types. What about the problems that come from improper humidity levels?




Plants take most of their water by literally sucking it up. However, very little of that water is used for building new cells. Most of the water just passes through the plants.


And, it goes out through tiny holes called stomata. The main role of the water in the plants is to keep them cool. For example, like the cooling system, you find in cars.




Like with cars, when there's no coolant, the engine breaks. The same goes for plants. Dry air creates the so-called high vapor pressure deficiency.


To elaborate a bit on that. On the inside, plants are filled with moisture. This gives them both the density and the ability to coll themselves down when the temperature is high.


Also, it's important to mention that the plants' breathe by exchanging gases with the surrounding air. This is done through microscopic holes, which, actually expose the plants to the environment.




When the air is dry, the plants "hyperventilate". This actually means that they release their moisture more than they should. They are actually struggling with "inhaling" the moisture.


Which, in the end, results with withered leaves and eventual death of the plant if the exposure to dry air is prolonged.


Also, dry air is the perfect ground for the attacks of harmful bugs and mildew.



Leona Maurer

Leona Maurer


Oh, the last sounds nasty...

Okay, more question and I will let you get back to your work.

What can you tell us about how to choose the best humidifier for grow room?

What is the most important factor when all things considered?




In my opinion, the most important factor is the size of your grow room.


I mean, type of the plants is also very important, but you can always adjust the mist output settings to match your plants' needs.


But, matching the mist output max power of the humidifier with the size of your grow room is extremely important.


Here is a general breakdown that works efficiently to grow rooms:


  • Small humidifiers, usually tabletop models with a 1-gallon water tank, for the grow rooms that are around 300 square feet, or for grow tents.
  • Medium humidifiers, tabletop models with a water tank from 3 to 5-gallon capacity, for the grow rooms that are about 350-500 square feet.
  • Large humidifiers, usually console models or tabletop models with extra large water tanks, for the grow rooms that are about 550-1000 square feet.


Leona Maurer

Leona Maurer


As promised, that was really the last question (laughing). I know how you are busy during the holidays season so I will leave you to your work. Thank you so much for helping out with this topic!




It was my pleasure, Leona. And thank you for deciding to have me as an expert.

I just hope that we made the topic of the best humidifier for grow room clearer to your readers. I am available to help you out if your readers have any further questions.


Best Humidifier for Small Grow Rooms or Grow Tents - TaoTronics Cool Mist Humidifier

best humidifier for grow room - TaoTronics TT-AH001 Cool Mist Ultrasonic Humidifier

Specific Features (Click Here To Know More)

The TaoTronics  Cool Mist Humidifier comes as a model with important features that every plant grower needs.


One thing is sure, with the noise level of just 38dB, the plants are not going to suffer from unnecessary noise pollution.


And we all know how plant's don't like bad noise.


Also, this is important for grow room owners who want to use the humidifier for their homerooms as well.


Your sleep will definitely not suffer if you use this humidifier while you sleep.


Furthermore, with its microporous cartridge, you can rest assured that your plants won't suffer from any harmful contaminants left out in the mist.


Likewise, the humidifier is mist adjustable, meaning, you can adjust the output levels and set the desired humidity levels easily.


And, the humidifier can last up to 15 hours allowing you to have access to pure air that could last the whole night.


Furthermore, it's great for grow rooms or tents because you can actually set the timer to start the humidification automatically when it's most suitable for your plants.


This allows you to improve the sleep/vegetating cycles and have excellent results with your plants.


Finally, with a 360-degree nozzle for the even humidification and an intuitive LED display, the humidifier is really easy to use.


All in all, a great and reliable choice for small grow rooms or grow tents.

Best Humidifier for Big Grow Rooms - Aircare MA1201 Humidifier 

best humidifier for grow room - Aircare MA1201 Humidifier

Specific Features (Click here to know more)

The Aircare MA1201 Evaporative Humidifier, as the name suggests, is an evaporative humidifier.


And, it has the power and capacity to comfortably humidify a grow room that is up to 3600 square feet in size.


Furthermore, this console-style humidifier comes with a system that has an included digital humidistat.


This means that achieving and maintaining the set humidity levels is easy and always perfect.


Also, there's no need to babysit this humidifier because it has the automatic standby feature that turn's off the humidification process when the desired humidity levels are reached.


And, you don't have to worry about wasting energy because the humidifier has the automatic shutdown feature when the water tank is nearly empty.


Finally, when it comes to cleaning and maintaining, thanks to the lack of wheels and belts, the entire process is simple and easy and requires minimal time and energy.

Best Humidifier for Medium Sized Grow Rooms - PureGuardian Ultrasonic Cool Mist Humidifier

best humidifier for grow room - PureGuardian Ultrasonic Cool Mist Humidifier

Specific Features (Click here to know more)

The filter-free PureGuardian humidifier comes with an Ultrasonic technology that is hassle-free when it comes to maintenance and additional costs.


Now, despite the lack of filters, the inside finish of the water tank prevents the mildew and germ development.


So, your plants will be safe from airborne pathogens.


And, speaking of the water tank, the capacity it comes with is one gallon. But, the output power of the humidifier is strong and it can push up to 3 gallons of water per day when set to highest mist settings.


This makes it ideal for medium sized grow rooms that are not bigger than 500 square feet.


On the other hand, when set on the minimum mist output settings, you can expect up to 70 hours of continuous use.


Also, you can expect features such as variable speed control and even essential oil use for when you want to take it into your room and have a relaxing spa day.


Everlasting Ultrasonic Humidifier (Special mention for medium grow rooms)

best humidifier for grow room - Everlasting Ultrasonic Humidifier

Specific Features (Click here to know more)

Well, for starters, it can also be used in your home as an aroma diffuser for those days when you just want to unwind and make a spa day at your home.


Second, for a table top model, the high mist output of 270ml per hour means that it can extremely comfortably humidify grow rooms of up to 500 square feet. And, this humidifier can be used if you want to achieve tropical humidity levels of some 60-70 percent.


To back up that high mist output, the manufacturer has included a 6-liter water tank so that it doesn't get empty after some 30 hours on max mist settings!


However, if you have a small grow room and set the mist control to minimum, you can expect up to 50 hours of non-stop working on just one tank filling.


Also, the inside of the tank is anti-bacterial treated so there's no risk of bacteria, mildew or mold development.


Needless to say that it is dangerous if the particles got released into the air your plants breathe.



Finally, this humidifier doesn't require an expensive filter, and it doesn't require a special (complicated) method for cleaning and maintenance.


We had another expert, only this time, it was my friendly florist who was willing to help us out in getting a better insight into all the angles we need to keep in mind when buying a humidifier for grow rooms.


What I would like to add in this final paragraph is that before buying a humidifier, you first need to determine the size of your grow room.


This way, you can make no mistake when choosing the humidifier because you will look if its mist output capacity matches the size of your grow room.


Also, once you know the capacity of the humidifier, you can see calculate the humidity levels it can achieve in your grow room.


This is important to know so that you can know if the ideal conditions that the plants you gro can be achieved.


For example, if you have tropical plants, you will need the highest possible mist output available.


In that case, the Aircare MA1201 Humidifier is your best choice as it can pretty much humidify a hangar.


And, just imagine how much mist it can produce in a big or medium sized grow room.


That's about it. Thank you for reading and feel free to submit any questions you might have.