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Want to learn from the ultimate guide to powdery mildew in cannabis? You've come to the right place!

Have you noticed some round patches of flour-like powder on the stem and leaves of your marijuana plants? Do you see white spots on your marijuana plants?

If you've witnessed any of the above situations, then you are most likely dealing with powdery mildew infestation. And if you don't act on time, you might have your entire cannabis plants ruined before long.

When dealing with powdery mildew infection on marijuana, your best strategy for getting rid of the cannabis molds is prevention. So as a marijuana grower, you might want to watch out for the early signs of powdery mildew.Typically, these white patches show up without warning or indication. Unless you address the disease almost immediately, the molds can easily spread to other parts of the plants: the leaves, stem, and buds. In the end, the buds are rendered useless.

However, before we proceed to understand the best ways to get rid of powdery mildew, we'll look at the definition of powdery mildew, or cannabis mold.

What is Powdery Mildew in Cannabis?

Powdery mildew (PM), otherwise known as white powdery mildew (WPM) or cannabis mold, is a type of rapidly reproducing fungus known to eat up affected cannabis plants. The visible sign of its presence is the formation of white or sometimes gray spots and flour-like powdery patches on the leaves of your cannabis plants.

It is believed that wind aids in the spread of powdery mildew. It can stay dormant on a surface until the time is right for it to strike. You can hardly tell if it's there until you see the signs, and it begins to spread. Powdery mildew affects other plants, but a different type is what you see on cannabis.

Because of how easy it spreads, even careful growers who exercise lots of precautions still experience powdery mildew. If you're a marijuana grower, you want to keep an eye out for signs of powdery mildew as they're not as common as many other disease conditions you're familiar with.

What Are the Signs of Powdery Mildew in Cannabis?

Powdery mildew is relatively easy to spot. You'll know your marijuana plantation is infested with powdery mildew when you begin to notice white flour-like or gray-colored patches or spots on the plants' leaves.

It also spreads very fast, especially with the aid of the wind. Its fast spread alone is another way to tell that you've got a powdery mildew problem on your hands. Mind you, as it spreads, it consumes everything in its path, leaving a trail of white patches behind. Once the spores of the fungi invade your cannabis buds, they can be difficult to remove.

The affected plants first turn yellow, then dry up and turn brown, after which they die off. If you want to maximize your marijuana yield, you must not let the situation get to this point. The most efficient way to fight off cannabis powdery mildew is by prevention.

5 Ways to Prevent Powdery Mildew in Cannabis Plants

Generally, the factors that cause powdery mildew are leaf-on-leaf contact, high humidity, poor airflow, and improper ventilation. To get rid of powdery mildew, the solutions must address these challenges.

Here are five proven tips to guide you in your efforts to deal with powdery mildew.

1. Spacing

Seeing how powdery mildew spreads and attacks your cannabis plantation, prevention is most reasonable. Whether you're an outdoor or indoor marijuana grower, the best and ultimate approach to getting rid of powdery mildew is by prevention.

Begin by allowing enough space between each plant while planting or while transferring the young plants from the nursery beds to their primary location on the farm.

2. Clone Only From Trusted Sources

Clean new clones of or take them to a lab where they'll be examined before introducing them into the farm.

This approach ensures you bring in only plants that are not infected into the fold. In other words, you can maintain a quarantined cannabis growing environment by ensuring new plants have a clean bill of health before planting them.

3. Proper Ventilation

Poor airflow can be detrimental to the health of your marijuana plants, just as excessive wind can be. If you're growing your cannabis in an enclosed facility, be sure to create room for the free flow of air.

The plants, too, should be adequately spaced apart as a powdery mildew outbreak can result from poorly ventilated environments.

4. Decontaminate All Equipment in the Environment Before Storage

Contaminants should be kept out of the growing facility as much as possible. You can use hydrogen peroxide to decontaminate all equipment whenever you use them. Decontamination also applies to personnel just as much as it does to equipment.

5. Control Humidity in the Environment

You should establish a proper and efficient method of dealing with humidity in the environment. This is essential for cannabis cultivation. Excessive humidity, for instance, is not ideal for growing cannabis plants. To create an environment with the right humidity level for cannabis cultivation, you might need to consult a HVAC technician.

Cannabis growers can check the spread of diseases and unfavorable conditions, such as powdery mildew, by maintaining the right humidity within the growing environment.

Master grower tips holding a

Symptoms of Powdery Mildew in Cannabis

Here are some of the symptoms you can expect to see when powdery mildew occurs on marijuana:

  • Pale coloration
  • White powdery patches in plant leaves
  • Wilting and dying plants
  • Visible growth of molds

Is Smoking Powdery Mildew Bad for Health?

Well, there's not enough scientific evidence to prove that smoking powdery mildew is dangerous to health, as the fungus is not a human pathogen. The worst that might happen is that you may develop allergies to it.

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As far as health issues go, when it comes to powdery mildew, the only concern is the health and appearance of your marijuana plants.

Bottom Line

There are many more ways to control the growth and spread of powdery mildew in marijuana. Some are chemical, such as fungicide sprays, while others are organic in effect.

However, the most potent method for getting rid of powdery mildew or mold on cannabis is holding it off. The moment it starts to grow, you might have issues stopping its spread.

To learn more about how to grow cannabis in your home, detect, and stop the growth of mold on your cannabis plants, simply enroll in our certificate courses today at the Cannabis Training University.

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