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How To Lower Humidity In Grow Tent in 9 Proven and Easy Ways

Plant care and cultivation are both an art and a science. Maintaining relative humidity as an indoor grower can be risky and problematic at times.

Many a time, a question is asked by pro gardeners: How To Lower Humidity In Grow Tent. Humidity is both the blessing and the evil of an indoor grow system.

When it comes to the quantity and quality of your indoor gardening yield, humidity, like temperature, plays a vital impact. However, if the humidity in the grow tent becomes too high, it may trigger your worst nightmare as a grower.

Indoor gardening novices frequently overlook this, resulting in powdery mildew, bud root, and other issues.

In this article, we will discuss how to lower humidity in Grow tent. Indoor growers who have done it before know how important it is to have the right humidity level in the grow tent to grow your plants successfully.

Elevated humidity levels can jeopardize your plants’ longevity, as well as your possibilities of high yields. The humidity level in the grow tent must not surpass 70%.

If you’re beyond that threshold, you’ll need to identify the source of the excess moisture and take steps to prevent the plants from suffering.

How To Lower Humidity In Grow Tent
My grow tent via Reddit

An Indoor Garden Guide on How To Lower Humidity In Grow Tent

Here are some tried and true methods that indoor gardeners have used to minimize humidity in their grow tents:

Avoid Overwatering The Plants

Remember that too much of a good thing can be bad. Avoid over-watering your plants to avoid having excess water in the grow tent.

This is more applicable to those who have your ventilation system on the floor. Also, over-watering contributes a lot towards the increase of humidity in your tent.

Use A Smaller Reservoir

One way to avoid over-watering is by using a smaller reservoir. However, this may not be applicable if you grow hydroponically or on Rockwool.

While it is important to supply the right amount of water for your plant, make sure the water doesn’t stagnate too long after it has been introduced.

Drastic temperature changes can happen in the grow tent with fluctuations in airflow, light cycles and watering schedules. This will only bring about disruptions to the life of your plants.

If you’re growing hydroponically or on Rockwool, make sure that the water in your reservoir is not staying in the same place too long over a day.

Adjust Ventilation Fans

Ventilation fans located on the floor will also cause humidity to rise. If you have this kind of ventilation system, it’s best to adjust them, so they’re pointing upwards. This way, you’ll have the chance to experience excellent air circulation.

Why don’t you try removing them from the grow tent? You can use ducting instead for an even better ventilation system, which will also keep excess humidity down.

This works best if you already have a proper exhaust fan. If you use HID lights in the grow tent, you may want to keep the exhaust fan on 24/7.

Disable The Exhaust Fan Until It’s Time To Ventilate

You should also try disabling your exhaust fan for an hour or two after watering. If you leave it running, all that moist air goes right into your grow room. You can then disable it again after watering, but make sure it’s back on in time before the lights go out.

Get Some Airflow Into The Grow Room

When growing indoors, fresh air is much needed after watering your plants. This moisture will only lead to higher humidity levels inside the grow tent without proper ventilation. If you use HID lights, you may want to let the air in the grow tent circulate once an hour after watering.

To do this, get a high-powered exhaust fan and keep it running for about 15 minutes after watering your plants. Ensure that the outside temperature is within 70F (21C) before letting any hot air inside your grow room.

Keeping The Right Temperature Is Crucial For Your Plants

The temperature inside your grow room should be kept at 70F (21C) or below. If you want to keep humidity at a minimum, it’s best to have air conditioning units, especially for the grow tent if necessary.

This will ensure that heat isn’t trapped within the grow tent, causing your humidity levels to rise.

Humidity can also raise in the summer months. If this is the case, you should try venting the heat by removing the plants from the grow tent or a high-powered inline fan.

Also, make sure that you don’t end up trapping humidity inside your grow room when lowering temperatures and over-watering at the same time.

If you’re doing the latter, it’s best to end this as soon as possible or else you’ll end up with a lot of humidity, which is bad for the health of your plants.

Use A Dehumidifier

You can also use a dehumidifier inside your grow room. This will keep humidity at bay and ensure that heat isn’t trapped within the tent.

You can set it up 24/7, but ensure it doesn’t cause the temperature to go over 70F (21C). The fan speed should be kept at an optimum speed to avoid excess noise.

You can also use a dehumidifier inside your grow room. This product will work especially well in the summer months when heat and humidity are at their highest levels.

It is important not to let too much humidity build-up indoors, as it may damage or kill your plants. For the most part, humidity inside a grow room should not rise above 70% or 50% during the winter months. It is best to take the necessary steps to fix this problem if it does.

Insulate And Seal the Grow Tent Properly

This is perhaps one of the most important aspects of keeping humidity levels down. To provide effective insulation, you need to cover every square inch of your grows tent, including the ducting, with heavy-duty material.

This will trap warm air from your lights and exhaust fan within the tent. However, be sure not to block any vents or windows, as this will end up trapping heat inside your grow room instead. Instead, cover only the ducting and lights.

Seal All Gaps And Holes Within The Grow Tent

One of the biggest causes of high humidity levels is the presence of gaps and holes in the grow tent’s structure. The warmth trapped within, combined with moist air from watering plants, will only increase the humidity levels inside the grow room.

This is why you need to ensure that the grow tent has a tight structure and is sealed properly with duct tape. The last thing you want to do is let any form of warm, moist air inside your grow room, as this will only affect the humidity levels.

Keeping your grow room at a constant temperature and lowering it by around 1-2 degrees is also an effective way of lowering humidity. This will ensure that your plants get the optimum amount of light, which is essential for their growth.

>> Related Post: How to Increase Humidity In Grow Tent? It Is Easy with These 5 Tips!

Final Remarks

Getting rid of humidity in your grow room is extremely important to ensure that your plants are healthy and happy. A tight structure will ensure that warm, moist air doesn’t end up leaking into your grow room and causing humidity levels to rise.

Also, make sure that you check for any signs of excess humidity. If your plants are experiencing drooping leaves or showing any form of mild to severe stress, you’ll need to take some action immediately.

Treating your plants with an anti-fungal agent should clear up any symptoms that may arise due to high humidity levels, but it’s best to keep humidity at bay before it becomes an issue.

By using these tips, you’re not just helping your plants grow healthy and fast, but you’re also saving yourself some money by having to spend less on fertilizer.

Now that you know how to lower humidity in grow tents, your plants will appreciate you for controlling the humidity levels for them.