How to Cool a Grow Tent?

When it comes to growing marijuana indoors, there are a number of things that need to be taken care of and ensuring that your grow tent remains cool is one of them. Ensuring that the grow tent is properly cooled is something that you as a grower really need to take care of and in this article, we will give you the best tips and tools on how to cool a grow tent. 
Grow tents are an essential element for anyone who plans on growing marijuana indoors. They provide you with a contained environment where you can test out various things while also ensuring that your grow lights are used to their maximum possible potential. Given that all the light is reflected on to the plants inside a grow tent, they also ensure that the plants grow better and provide higher yields. Grow tents also help hiding your plants from public sight and also help contain the smell if you use a carbon filter with them. There are a number of other benefits of grow tents, such as keeping pests and insects away, etc. However, keeping the tents cool is one thing that you really need to take care of!
Over the course of this article, we shall take a closer look at why grow tents heat up, why do you need to keep them cool, and then how to keep grow tents cool – the best tips and tools to ensure your tent doesn’t heat up. We hope that this article helps you gain a better insight on cooling your grow tent. 

Why Do Grow Tents Heat Up?

If you’ve yet to build your grow space, that’s cool. But in case you already have one, then a high temperature might be troubling you badly. So, before proceeding further, take a look at the most possible reasons for it-

Improper Ventilation

Take a look at the outdoor garden or the local park. What’re the other things that mother nature is providing them apart from the sunlight? You’re right, it’s the natural air flow. Which is termed as Ventilation in case of indoor growing. Lack of proper ventilation comes with several discomforts for the plants. And a higher temperature is the #1 of them.

Too Many Heat Producers

Lights are the greatest heat source in a grow room. But there are items that emit heat that circulates around the space. Examples- Light Ballasts, Large Pumps, etc.

Not-so-Insulated Location of the Grow Tent

I’ve been a grower for past 2 years. And from the very beginning, I grew plants in my basement. Growing in such an insulated area helped me to get at least 5°F less temperature than the same setup planted anywhere in the house.
And when the plants get overheated from one or many of these reasons, that begin to show signs of stress. Which results in a low yield of flower or fruit. Go through the next sections of the article, if you’ve to know some real-time ways to beat the heat in your grow space-

Why Do You Need to Keep Grow Tents Cool?

You need to keep your grow tents cool because having an excess amount of heat building up in your tents will be detrimental to the growth of your plants. If your grow lights are heating up too much, it could result in the top of your plants starting to burn off, or it could also result in more dangerous consequences including your grow lights either getting damaged due to this excess heat, or sometimes even catching fire. While fire-related incidents have greatly reduced over the past few years, there’s still a risk of that if there’s no proper cooling mechanism. In addition to that, if your grow tent is heating up too much, it would also result in a slower and stunted growth for your plants and they would need more water as well. While a moderate amount of heat is good for the plants, too much of it is bad. 

How to Cool a Grow Tent? Tips and Tools to Keep Grow Tents Cool
Install a Quality Ventilation System

Using inline and exhaust fans are one of the best solutions to ensure that the grow tent does not heat up so much. These fans make sure that while fresh air is pushed into the tent, the air that is inside is pushed out as well. This combination ensures two things – there is a constant flow of fresh air inside the grow tent, which is very important for the growth of the marijuana plants, as well as that the hot air keeps moving out. The exhaust ensures that all the air that is accumulating inside the grow tent is circulated out of the tent and making sure there’s no hot air that remains inside. A well-set combination of inline and exhaust fans can result in the best possible scenario for the growth of your plants where the air is just perfect levels of warm but not so hot that it causes any damage!

Consider an Air Conditioning Unit

Air conditioning is the simplest means to ensure that temperatures remain low. If you have a small growing setup, one small Air Conditioner should be good enough but if you have a growing setup which is too big, you would perhaps require an industrial grade cooling solution and a bigger air conditioner, perhaps one with big pipes running all over your grow room. However, Air Conditioners ensure that temperatures remain low and are the easiest way out for growers who want to avoid overheating of their grow tent. The one drawback that using air conditioning has is that the cost of electricity needed to run them tends to be too high, especially if you are growing on a large-scal

Using Carbon Dioxide

As easy as this sounds, using carbon dioxide can be very tricky as it is really only helpful when the normal optimal temperature of a grow tent has already been exceeded. From basic biology, we all know that carbon dioxide is pretty much important for plant photosynthesis so the catch is that when you increase the level of carbon dioxide in your grow tent the level spikes and helps plants to perform more efficiently and thus maintaining normal function even in a hotter condition.

Manage Heat in a Grow Tent by Managing Heat Around the Grow Tent

While the grow tent needs to have a good air circulation, another way as to how to cool a grow tent is to keep the grow room in itself cool. Using a proper system of exhaust in the grow room is a good solution to keep the grow room cool. If the grow room is cool, the tents will also be quite cool. However, you need to ensure that your grow tents have a good carbon filter, otherwise, the smell of weed will be all over your neighborhood!

Air-cooled lighting

The mechanism of action of this is pretty much easy, all it does is that it uses an extraction fan to pass air over the lamps and then removes warm air from your grow tent using aluminum or acoustic/insulated ducting. The insulated ducting is better than the aluminum due to the fact that it does more cooling than the aluminum. So in summary, the air-cooled lights possess a glass bottom which creates an air fitted channel. Cool air is released through this channels and over your lamps to eradicate heat.

Using Water Cooled Lighting Systems

Now this is something we rarely see! But water-cooled lighting systems are great for keeping a grow tent cool. This is because grow lights are one of the biggest sources of heat inside a grow tent and using water-cooled lighting systems ensure that the temperature of these grow lights remains under control. These have also been found to be better at cooling the temperature of the grow lights when compared to air-cooled grow light systems. 

Using LED Lights

Greenhouse- When growing inside just won't happen but you don't have tons of room outside either, think about building or buying a greenhouse. In a greenhouse you get all of the benefits of growing outdoors (temp, abundance of light) with the added benefit of indoor growing (supplemental lighting and ventilation)

In a greenhouse you tend to save money on lighting by utilizing the sun’s light, which is actually one of the most optimum light sources available
In the event you need extra lighting you only need lower powered grow lights to hold you over until the sun comes back out (though you can always use high powered LED or HID's, too)
There's also plant training techniques like Light Dep that help you get bigger plants in greenhouses
Because they're already partially acclimated to outdoor environments, you have the potential to take greenhouse-grown plants out of the green house and plant them directly outside without lots of training like you would bringing indoor plants outside.


To sum up, everything that has been stated, the problem of how to cool a grow tent is one that is faced all over the year especially during the hot period and its effects can be quite devastating because it could drastically slow down growth, increase moisture loss, hamper plant growth and affect seed germination. The importance of keeping the temperature inside your grow tent within optimal temperature cannot be overemphasized.  Having excess heat in your grow tent does a lot of harm to your plants for example without a doubt, excess heat can kill cannabis, especially during the flowering phase.