4 Best Grow Room Dehumidifiers

Dehumidifiers are commonplace appliance from humid Florida homes to the damp basements of the Midwest, and now they’ve found another home—your grow room. Dehumidifiers play an important role in keeping your plants healthy and happy indoors, but with them being such a widespread piece of equipment, there’s a lot of different options in the market.

You can get dehumidifiers small enough for a grow tent or in large multi-piece hydroponic system industrial setups. Which one is right for your grow room? We’ve got a few recommendations to narrow down your search.

Best Dehumidifiers for Grow Rooms

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This product comes in 30, 50, and 70 pint options, though our pick is the 50 pint. It’s a favorite among the indoor grower’s community. The two larger options come with a digital screen and electric controls make setting your desired humidity easy, and the six-foot-long cord is a great additional feature that makes it that much easier to incorporate into your grow room without added extension cords.

Some of the favorite features noted by buyers is its ease of cleaning, low volume, and digital readout. Most buyers have to change the water receptacle once per day, which isn’t a big deal for a grow room, since you’ll be in there at least once a day to check on the other parameters of the grow room anyway.

It has a washable filter that helps to remove bacteria from the outputted air, which is a great first line of defense for a grow room. Frigidaire is a respected brand, and they’ve once again followed through with a reliable product.

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Much like the Frigidaire, this dehumidifier comes in several different sizes, although this one is the smallest at around 30 pints. This dehumidifier will run continuously and automatically shut off when the receptacle is full.

Alternatively, you can place the dehumidifier over a drain, remove the receptacle, and allow the dehumidifier to flow directly into the drain to avoid shutoffs. This dehumidifier also touts a removable, washable filter that the manufacturer recommends you take care of once a month.

Buyers really love how effectively this dehumidifier does its job. It’s easy to use, quiet, and beginner-friendly. Reviewers have rated this model highly for energy-efficiency, so you know you won’t be shelling out a huge sum every month to take advantage of this dehumidifier’s power. And if something goes wrong, reviewers have said they’ve had great luck working with the manufacturer to fix any issues.

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If you only need equipment for a small space and you’re not looking to invest in some of the high-power larger dehumidifiers, this is the one for you. You’ll shave off some of the cost in exchange for a lower capacity machine, but for smaller gardens, that shouldn’t be an issue.

This unit runs at 18 ounces per day and comes with an auto shut-off feature that we love with the other two models. One of the features this model comes with is a large 52-ounce receptacle that will let you set and forget this mini portable dehumidifier.

Reviewers love how quiet this dehumidifier is and how easy it is to use. The design has been streamlined to make sure that this tiny piece of equipment is as easy to use as the high-end large models. Buyers also noted its energy efficiency and high-quality material.

Looking for an industrial size setup? Check out this site for a few high capacity options curated specifically for grow room use.

Best Budget Dehumidifier

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For small low budget operations, this is our top choice for dehumidifiers. It automatically shuts off when the receptacle is full and also when the humidity falls below 40%, which won’t cause issues for your plants.

One of the sacrifices you’ll make with choosing the low budget option is that you will have to dump the receptacle more often. That being said, buyers love this dehumidifier for its quiet ease of use and the bang for your buck.


Do I need a dehumidifier in my grow room?

A dehumidifier is an important piece of equipment for all grow rooms. Every plant emits water molecules into the air as part of their photosynthesis cycle, and so a closed room filled with plants can quickly become very humid. If you don’t lower the humidity, your plants run the risk of contracting fungal diseases, which thrive in humid environments and can prove deadly for your crops.

What is the best humidity level for a grow room?

Most plants will do well around at 45-55% humidity, but a wider range is OK too. This keeps the foliage from drying out in too-dry air while warding off potential harmful fungi or bacteria that enjoy more humid environments. Learn more by checking out our post on the ideal temp and humidity for a grow room.

What size dehumidifier do I need?

The dehumidifier’s size should be in line with the size of your grow room and the number of plants in the room. Big rooms filled with lots of plants will need big dehumidifiers, and small rooms with just a few plants will need smaller dehumidifiers.

You can calculate the dehumidifier requirements of your grow room by figuring out how much water your garden will use up in one full day in pints. Whatever value you get is the approximate dehumidification requirements for your grow room.

Dehumidifiers will tell you in the product descriptions what their dehumidifying power is, so make sure to check those numbers against your requirements to be sure the product you choose is rated for your setup. Sometimes, you may need to use more than one dehumidifier to appropriately accommodate the needs of your grow room.

Where should I place the dehumidifier in grow room?

If you will only be using one dehumidifier in your setup, make sure it is in the center of your grow room. This allows for uniform airflow through the room so all of your plants are getting optimal humidity. For multiple dehumidifiers, it’s important to have them equally spaced and away from the walls for similar reasons.

It’s also recommended to install dehumidifiers close to the light sources such as LED grow lights. This could mean installing dehumidifiers coming down from your ceiling. Although this may require an extra couple steps of setup, it prevents air circulation problems and keeps your room running efficiently in the long run.

Will a dehumidifier make a room cooler?

Dehumidifiers do not produce cold air, but because it removes moisture from the air in your grow room, it allows the air conditioning system to work more efficiently and eliminates some of the mugginess associated with humid air. This can give off the appearance of a dehumidifier cooling a room.

Grow room temperature, humidity, and fungal risk are all closely related, so it’s important to understand how to keep fungus risk low, especially if you are moving a summer outdoor garden indoors for the winter, since you will be used to the care associated with warmer, less risky environments.

Higher temperature air can hold more water and become quite humid. When this air cools, it can no longer hold onto that water, and so the water vapor condenses into water droplets. The cold air is less humid, but it is harder for water to evaporate from your soil and the water that used to be in the air is not stored in its own container as with a dehumidifier, but is deposited all around the room, including onto your plants.

This can put your plants at risk of fungus and rot. This is why we get morning dew. The warm, humid air from the day cools overnight, depositing water droplets all over the grass.

How can I lower the humidity in my room naturally?

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Lowering the humidity of your grow room without dehumidifiers can be done through ventilation, such as an open window or using an exhaust fan. You can also use charcoal, which is naturally absorbent and will suck the moisture out of the air just by sitting around.

Neither of these methods, however, are as effective as using a dehumidifier and allow you to maintain stable conditions in your grow room. Charcoal doesn’t work as quickly (unless you plant to use a whole bunch) and opening a door or window could result in temperature fluctuations that hurt your plants’ ability to grow.

Do dehumidifiers use a lot of electricity?

Larger dehumidifiers, of course, are going to use more electricity than smaller ones. As a general rule, you should plan to budget about $15-$20 worth of electricity per month per dehumidifier. Going off this, you can assume that it will be more energy efficient and cheaper to use one large unit rather than a few smaller ones, so make sure to invest in the higher power equipment if you are able.

Dehumidifiers are an important piece of every indoor grow room. Although it’s certainly not the first thing that comes to mind when you think of gardening essentials, it could be the difference between a successful crop or a lethal fungal outbreak, and it’s definitely worth the investment.

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