Does Ozone Kill Powdery Mildew?

Does Ozone Kill Powdery Mildew

In horticulture and agriculture, ozone is gaining popularity as an effective means of healing plants against fungal attacks, especially powdery mildew. But if you have never used this method, you will wonder does ozone kill powdery mildew.

It is possible to kill powdery mildew with ozone. All thanks to the unstable oxygen molecule in the ozonated water that reacts with fungus to treat the powdery mildew. However, it only works if you properly use the water. So, for your plant’s healthy growth, I am here to walk you through the process. 

Does Ozone Kill Powdery Mildew?  

Ozone or ozonated water can kill powdery mildew. For that to work, you need to use ozone water for plants affected with fungal infections or powdery mildew. 

Once the plants absorb the water, the unstable oxygen molecule in the water bonds with the fungus on the leaves. And gradually, this chemical bond kills the fungus. Without the presence of fungus, the powdery mildew does not spread any more. For more insights, head to the clip:

How to Use Ozone to Kill Powdery Mildew?

You will need ozone-infused water to treat the powdery mildew. You can either buy the liquid online or make it at home. As it is not available in all stores, you can follow the steps below to make ozonated water and use it:

Step 1: Preparation 

The most effective method of making ozonated water is to use an ozone generator and oxygen source. So, from a reliable and certified store, buy the generator, ozone regulator, and oxygen tank. And attach the ozone regulator to the tank securely. Then, fill the clean water in a container. 

Does Ozone Kill Powdery Mildew

Step 2: Set the Generator 

In a well-ventilated area, place the generator. If you want to use ozone in a grow room, make sure the room receives enough sunlight. Attach the oxygen tank generator to the generator as per the instructions in the user manual. You will need silicon tubing to connect them.

Does Ozone Kill Powdery Mildew

Then, take another silicon tubing and attach one end to the generator. And connect the other end to the water container. Now, plug in the generator and press its Start button. Note that you may need to attach two tubing in the container if your generator manual requires so. 

Step 3: Place the Water in Backspray

Once you run the generator for ten to twelve minutes, the ozonated water will be ready. Immediately fill it into a garden back spray. Because after thirty minutes, the ozone will disappear from the water. Do not forget to wear safety gear while handling the water. 

Does Ozone Kill Powdery Mildew

Step 4: Spray on Plants 

Spray the water on the infected plants, especially on their leaves. Because Powdery Mildew mostly forms in tender parts of plants. Use the water in a very little amount. Or else a high concentration of ozone kills plants. 

Make sure you apply the liquid on a clear day so that rain does not wash off the substance. You can repeat the step once or twice a week to get rid of Powdery Mildew.

If you are not so good with handling these tools and monitoring chemical reactions, conduct the process under a supervisor’s guidance. It will be safe for you. 

Is It Safe to Use Ozonated Water to Treat Powdery Mildew?

Exposure to high levels of ozone is harmful to both plants and humans. So, before treating powdery mildew with Ozone, consider the following factors below –

Does Ozone Kill Powdery Mildew

1. Choose the Correct Setting

For making ozone water choosing the correct space is a must. Or else it gets difficult to control the ozone concentration level in the water. So, always choose a spacious room away from flammable objects.

If you use powerful devices such as an oxygen tank and generator in a confined place, it will increase the concentration level in the ozonated water. And such water is harmful to your olfactory senses. It can affect your odor perception.

The worst is you might not be able to properly smell around you if you are exposed to high levels of ozone in the environment. But a spacious setting with enough sunlight and air reduces the possibility. So, while making the zonated water ensure you have the proper place to do so.

2. Protect the Healthy Plants

While sparing ozonated water on the Powdery Mildew infected plants, you must avoid spraying it on the healthy vegetation nearby. Otherwise, the water can penetrate the roots and kill the healthy plants.

Before applying the liquid, cover the nearby trees with a tarp. And avoid applying the water on a rainy day. It will prevent the solution from getting mixed with the soil. If the ozonated water reaches the soil, it can damage the soil structure.

Also, the nutrients available in the soil can decrease in quantity due to ozonated water. So, you have to be very careful not to drop the liquid into the ground.


If you have never worked with ozone, it is usual to wonder does ozone kill powdery mildew or not. Well, this solution can be either a hit or miss, depending on the quality of the ozonated water. If the water is not infused with enough oxygen, it will not work. 

So, to keep the ozone concentration at the appropriate level, I’d highly suggest using an ozone test kit or meter. Its manual has the necessary instructions to measure the ozone level present in the water.

Frequently Asked Questions (F.A.Q’s):

Is Ozone effective in treating Powdery Mildew?

It depends on the ozone concentration present in the ozonated water. If the powdery mildew has spread, you will need a moderately high ozone concentration to treat the disease. 

Can you prevent powder mildew from growing back with Ozonated water?

It is not possible to prevent fungal infections in plants by spraying ozonated water. You will need to use fungicides or other herbicides on the plant leaves and roots to save them from such diseases. 

Can ozone completely remove Powdery Mildew from plants? 

Ozone cannot eradicate Powdery Mildew completely. But it can be effective in preventing the fungal infection from spreading to other parts of the plants. 


Md Biajid

Meet Mia Biajid, a passionate nature lover. Particularly, he has a deep-rooted connection to the plant. Mia loves to spend time exploring forests and uncovering the secrets held within trees. He always inspires others to appreciate and protect our precious part of the ecosystem.

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