Growing tents are very popular because of their convenience and efficiency. They are able to provide the right conditions for any plant.
The ideal humidity in a grow tent is in the 40-70% range. More precise values depend on what stage your plants are at.
Below we will look at all aspects of grow tent humidity in as much detail as possible.
Why is humidity important for plants in a grow tent?
Humidity is very important for most plants because it prevents the leaf blade from drying out. Seedlings are the most vulnerable to insufficient humidity.
If you are just starting out and have potted seeds, the humidity in your grow tent should be 70% or even a little higher. This should be until the plants have built up a good root system.
The same applies to cuttings. If you are rooting cuttings, make sure you have at least 70% humidity in your tent.
When the seedlings become plants, the humidity can be reduced. A humidity of 50% is optimal for most plants.
Some plants need about 40% humidity to mature. But vegetables, herbs, or leafy greens are best at 50%.
How to increase or decrease humidity in a grow tent?
To adjust the humidity in the grow tent, you need a device to measure it. The best device for this purpose is the hygrometer.
These devices are available for purchase at garden centers and online. You can choose from both analog and digital models. However, prefer the higher-quality models as they will give more accurate data and last longer.
Let’s say you find that the humidity is too low and you need to increase it. The best way to do this is to use a humidifier. You can also buy such devices online and they are very effective because they quickly humidify the air.
But if, on the other hand, you find that the air in your grow tent is too humid, you have to use a dehumidifier. This is a bit more expensive and complicated than a humidifier, but it is just as effective.
Just turn it on for a few hours and the humidity in the tent will drop drastically. Avoid, however, lowering the humidity too much as this can lead to negative results.
What happens if humidity is too low in grow tent?
Low humidity in the grow tent can have a bad effect on plant growth. Leaves evaporate the moisture all the time to keep their surface moist and at the same time cool the plant if the environment is too hot.
Leaves will evaporate too much moisture if the humidity is low. At some point, there will be a water deficit inside the plant and it will stunt its growth. As a result, you won’t get the yield you want.
What are the symptoms of low humidity?
The first symptom that can occur due to low moisture is that the plants stop growing. They will stagnate until the environment improves.
What will follow is the yellowing and shriveling of the leaves from the tips or along the edge. The leaves will slowly dry out and turn crispy brown.
If there are flowers on the plant, they will quickly shrivel up and turn crispy brown as well. Plants with thick leaves may develop cracks.
What if the humidity is too high in grow tent?
If the humidity in the grow tent is too high, the plants will start to get sick. A humidity of more than 90% is considered high. Also a sign of high humidity is water on the walls of the tent.
The first disease that usually occurs, in this case, is gray mold. This is a very common disease, the symptoms of which are gray mold on the leaves and stems. Plants affected by this disease can die quickly.
If this happens in your tent, remove all diseased parts of the plant. Spray the plants with a multi-purpose fungicide. Reduce humidity in the tent and make sure it is well-ventilated.
Also, high humidity can cause dry brown spots to appear on the leaves. This is a fungal disease that progresses fairly quickly. It should be treated by spraying with fungicide and reducing humidity to 50%.
And the most unpleasant is a bacterial infection of plants. It happens very often in humid environments. It is almost impossible to treat such diseases.
Symptoms of bacterial disease are large moist areas on the leaves that are dark in color. If this happens to your plants, it is best to throw them away.
Do fans increase humidity in grow tent?
Fans can slightly increase the humidity in the grow tent. This is because moisture often accumulates in certain areas of the tent, such as the floor or walls. At the same time, the air humidity may not be very high.
If you turn on the fan, the air currents will distribute moisture throughout the tent and the humidity will increase slightly. It is important that the fans run at minimum or medium power. This is quite enough to keep the humidity even in all parts of the tent.
At full power, the fan is able to push the air out of the tent. This will cause a decrease in humidity, so avoid doing this.
Also, the soil in the pots will dry out a little faster with the fan on anyway. So you will have to water the plants a little more often.
The clear advantage of using a fan in a grow tent is that it produces air currents. This greatly reduces the risk of fungal disease.
Will a bowl of water increase humidity grow tent?
A bowl of water can increase the humidity in the grow tent a bit. However, place at least 4 bowls in each corner to have a bigger effect. Also, turn the fan on to minimum power and this will increase the humidity even more.
You can also hang wet towels in the tent. This will greatly increase the humidity in the air. But you will have to wet them often.
Another way is to spray the plants with water. Use an ordinary hand sprayer filled with clean water. But do not overdo it; the leaves should not stay wet for a long time.