Ideal Temperature and Humidity for Grow Tent

The image show water droplets over a plant demonstrating humidity

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We all have thought of buying a grow tent. It is easy to manage our hydroponics inside a grow tent. Grow tent gives your plant a controlled environment. Also, the grow lights can be bought with exact specifications and you can be sure that no light is getting distorted away as everything is concentrated inside that grow tent. 

Today we are going to discuss what should be the ideal temperature and humidity(RH) inside my grow tent?

In a nutshell, the ideal humidity of the grow tent should be 95% in the germination phase, 60% in the vegetative phase, and 45% in the bloom phase. The ideal temperature should be in the range of 68 to 80 degrees Fahrenheit. 

When we talk about creating an ideal environment around our hydroponic plants, we talk about proper lighting conditions and nutrients. The other two important factors that make a perfect controlled atmosphere are temperature and relative humidity (RH). Both of these play a massive impact on the end result of your grow.

Germination Phase

germination in grow tent

When you first get started you definitely want to keep the humidity up quite a bit higher around 95%. The reason for this is, the plant doesn’t have any roots developed yet so we need to supply all the moisture.

It takes up all the moisture in the air with the help of the stomata in the leaves. In a layman language, stomata are small pores in the leaves which helps the plants to exchange gases from the surroundings.   

In the cloning stage, you definitely want to use a humidity dome this will help keep the humidity quite a bit higher and keep it all locked into one area 

Vegetative Phase

Once we get the roots developed the plant starts to get into the vegetative stage (the period between germination and flowering) and now we can reduce the moisture inside our grow tent to 60% as the roots will start absorbing more moisture from the nutrient solution and leaves will absorb more carbon dioxide.  

In the case at any point in time, the humidity falls below these levels and especially in the germination phase, you can expect the plant to show stunted growth due to the fact that the stomata functioning will be reduced. 

Also Read “How to Remove Algae in Hydroponic System

Bloom Phase

Once we get into the flower/bloom stage now you can bring the humidity even lower to around 45%. The reason behind this is that too high of humidity and especially in a nice thick canopy could potentially result in bud rot. As a hydroponic gardener, you don’t want to ruin your harvest right? So, keep an eye on the humidity levels.

How to Control Humidity?

You must be wondering how you can control humidity inside your grow tent. 

If you are a beginner and you only have just 2 or 3 plants inside the grow tent, the humidity level may not fall too much but still, you want to maintain the levels.

You can use an old trick. You can keep bowls of water inside the tent or some plastic tub with a greater surface area filled with water. You can also spray water inside the grow tent from time to time. But this is a very slow and exhaustive process.

humidity inside grow tent
Image Source – Vecteezy

The best way in which the humidity can be controlled is through dehumidifiers or humidifiers. To maintain the uniformity of the controlled environment that you have built you can get a humidity controller or a temperature controller or some all-in-one plant-specific units. These units will help you preserve your atmosphere for a longer duration. 

So, if you are growing something that requires a completely controlled environment then you need to have the ideal airflow circulating inside your grow tent. You need to have an energy-efficient hydroponic system to reap a good harvest at optimum cost.

Also, Read “DIY 5-Gallon Bucket Hydroponic System to Grow Tomatoes

Ideal temperature in grow tent

If you don’t have the ideal situation in your room you really will struggle with having your overall production in your garden. The ideal temperature is between 68 and 80 degrees Fahrenheit. That being said you should keep in mind that the temperature at any point should not exceed 86 degrees Fahrenheit. If the temperature exceeds this limit your plants may stretch more i.e more stems than leaves and you don’t want that. 

If you face some temperature issues in your grow room then the best way to control them is with artificial support. You can use cheap exhaust fans to take out the heat or if it is falling then an electric heater would work. If the grow tent is big multiple fans may also be required to circulate the air and take out excessive heat.  

Sometimes, you may have to set these devices on timer controls. You can also utilize something like the pulse app. The main point here is that you need to control the temperature and humidity inside the grow tent whether you are there or not. 

How to measure humidity?

It is recommended to install a Thermo hygrometer inside your grow tent. This will help to monitor the temperature and humidity constantly. Lots of these devices are available on amazon at dirt cheap prices. I have given a link to the one that I recommend and a lot of growers use. It is affordable and really works well. 

Featured Image Credits – Free Stock photos by Vecteezy