How To Lower Humidity In Grow Tent? (9 Effective Ways)




How to Lower Humidity in Grow Tent

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One day, upon returning from work, Mark noticed something unnatural on the plants in his grow tents. He found some plants with powdery mildews and bud molds, some with rotten flowers. He was astonished. Why did Mark face the problems?

Well, Mark is not alone. Every year thousands of people face these same issues. 

Experts consider high humidity as the primary agent behind these sorts of problems in a grow tent. Many people have successfully avoided these unwanted issues. They did so just by controlling the moisture of the tent effectively. 

Here, we have discussed how to lower humidity in grow tent.

After reading this article, you will have a clear view- why you need to reduce humidity, what causes a humid environment, and how to combat high humidity.

Why Lower Humidity?

At first, we need to know what humidity is. Generally, humidity refers to the number of water vapors in the environment. Humidity itself is not a bad thing. But it poses threats to tent planting when it goes above a specific range. The ideal temp and humidity for grow tent are respectively 20-30C and below 70%. The dangers of high moisture include-


Pests And Diseases

High humidity invites pests and microbes, which causes diseases like bud molds and powdery mildews. Solving humidity problems often solves these issues.

Effect On Metabolism

Excess humidity harms a plant’s ability to intake Carbon-di-oxide. As a result, the plant cannot do photosynthesis properly, which affects the plant’s whole metabolism.

Rotting Of Buds And Flowers

Too much humidity presents a genuine threat to plants. It harms relatively delicate parts like buds and flowers. Bud rotting and flower rotting are common in high humid grow tents.

Inhibit Growth Rate 

Effective control of humidity is a must for the proper growth of plants. Without controlling moisture effectively, the growth rate would not be satisfactory.

Low Water Intake Of Roots

There are already enough water vapors in the high humid air. And so plants can not evaporate the water. They tend to intake less water than required.

Low Plant Yield 

Beyond the ideal range of humidity, plants can’t do their regular metabolic activities. That affects the outcomes of plants. High product is one of the most important goals of any planting. So it’s essential to maintain a proper humid environment.

What Causes High Humidity?

Before knowing how to lower humidity in grow tent, we have to understand what causes high humidity. The typical causes of high humidity include-


While watering is a must for growing plants, overwatering is very harmful. Sometimes it makes the soil more moist than usual, which increases humidity.

Free Water Surfaces: 

Open water surfaces are directly responsible for humidity. Water evaporates, and so the surroundings become humid. If there is any water pot, you should cover it.


Transpiration is a natural process where plants release water vapors into the air. Plants imbibe water from the soil. And it makes the air humid.

External Environment: 

Though grow tents are not connected with the ground, the outer environment affects grow tent plants. If the external humidity is high, grow tents tend to have high humidity.

No. Of Plants: 

Too many plants in a small space increase humidity. While planting, you should always consider how many plants you have in your grow tent.

Size Of Grow Tent: 

Large grow tents do not get humid so quickly as small grow tents. It also comes down to the density of plants you are growing. 

Effective Ways: How To Lower Humidity In Grow Tent?

To lower humidity, we have to address the causes of high humidity. All of us will not face the same sorts of problems. You have to identify which situation you are facing. Follow the advice and learn how to control humidity in grow tent. But if you consider the cheap way to lower humidity in Grow Tent please check this link.

Do Proper Ventilation 

By ensuring adequate ventilation, you can decrease humidity. Ventilation makes sure that the trapped air inside the tent has a link with fresh air. You can use fans for airflow.

Do Proper Insulation 

The high temperature of a region can be the cause of high humidity. So you have to check whether your grow plant has appropriate insulation. Doing so will shield the plant from outside moisture.

Use Air Conditioners 

Air conditioners can improve the quality of air and make it low humid. If you face high humidity, make sure you have an air conditioner. However, buying an AC is costly. But it can provide desired results

Use Dehumidifiers 

If you face high humidity frequently, a dehumidifier is right for you. There are many dehumidifiers for grow tents available in the market. They vary in size and power. You have to pick the one that best suits the grow tent’s size.

Remove Stagnant Water 

A stagnant open water source will increase the humidity of the tent. So to reduce humidity, you have to get rid of free water sources.

Apply Water-Absorbent Soil  

There are many soils in the market that absorb water. Applying these soils in plants will decrease humidity. And improve plants’ growth.

Reduce Plant Density 

The high density of plants will result in high humidity. So to lower humidity, you have to reduce the number of plants in a grow tent.

Control Overheating Lights 

Lights that produce heat can cause temperatures in the tent to become high. You have to control the temperature to control humidity

Defoliate Plants 

Large leaves release more vapors than small ones. Sometimes removing the larger leaves may decrease humidity. 

Growing plants in grow tents is a delicate task. It requires painstaking efforts. High humidity can wipe out all your hard work. So it would help if you consider this matter with sincerity. Knowing how to lower humidity in grow tent will give you a significant edge over others. 

But before lowering humidity, you have to look for the signs of high humidity. Then you have to find out the main agents that are causing high humidity. Sometimes low-cost approaches will solve the problems. But if they do not work, you must be prepared to invest in buying a humidifier or an AC. After all, controlling humidity is a must for growing plants in grow tents.

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