Powdery Mildew is a widespread fungal condition that affects both outdoor and indoor vegetation, especially Cannabis plants. Powdery Mildew will attack your plant at every stage of its growth. Powdery Mildew can affect seeds and clones as well. In reality, Powdery Mildew clones are so common that when mother plants become contaminated with Powdery Mildew, the clones become infected as well. If you’re adding new clones to the system, make sure to thoroughly test them and reject those that have Powdery Mildew.

Powdery mildew can be identified visually by white powder spots on the leaves, roots, or stems. They appear as small slivers or vast swaths. While powdery mildew is most commonly found on the surfaces of leaves. This fungus can also be found on stems, plants, as well as the edges of leaves. Close examination of the white residue reveals that it will be slightly elevated and sticky.

Powdery mildew is capable of infecting cannabis by causing tiny spores to germinate. Such spores are caused by wind, infected areas, or even the plants themselves, so in the right atmosphere, they quickly multiply to delay growth and destroy harvests.

If left unchecked, the fungi that cause powdery mildew will spread quickly into the plants, mostly during the final few weeks of growing. Bud rot may develop during or after harvest, wreaking havoc on months of labor and rendering the finished product unsafe for human utilization.

Powdery mildew affects both leaves and crops, and if left untreated, it may severely damage cannabis plants, although it isn’t often visible. The majority of powdery mildews also have a 4-7 days thread window during which they are undetectable to a human eye. Be aware because spores multiply and eventually spread! It is yet another reason why spending more time in the garden and paying close attention to the plants is essential to success.

Powdery mildew resistance varies by cannabis variety; however, all plants must be handled with Powdery Mildew preventives during the vegetative growing process, as having Powdery Mildew in semi flower is nearly impossible. If you don’t protect the vegetative plants from Powdery Mildew, you’ll have a much harder time battling Powdery Mildew also during the flowering stage.

In this article, we will cover everything you need to know about Powdery Mildew’s cannabis disease. Continue reading to learn more.

Powdery Mildew Cannabis Disease Symptoms

The symptoms of these infections include whitish, powdery stains on the top or bottom plant leaves. Powdery mildew could cover whole leaves surfaces, including leaves petioles, and even flower buds could be infected. Inside the spots of powdery mildew, a chasmothecia becomes evident as they transform from yellow into black over time. This disease can affect plants as well as buds at any stage of development.

How Does Powdery Mildew Look Like?

You’ll notice a white flour-like dusting covering the plants once Powdery Mildew has contaminated them. Powdery, round white patches develop upon leaves and stem in the beginning. Powdery mildew usually occurs mostly on the upper portions of the stems, but it can also be shown on the underparts. Harm to young vegetation is more likely, but it may also inhabit older tissues before drying the affected leaves completely.

Leaves may become deformed, fall off, or bend in some cases. Powdery mildew can eventually cover the majority of the leaves in white areas. The leaves, rising tips, as well as buds will all be disfigured. Powdery Mildew symptoms typically show up at the time of harvest.

What Causes Powdery Mildew on Cannabis?

Powdery mildew is caused by environmental factors such as rising humidity, inadequate and unfiltered ventilation, as well as the introduction of contaminated clones/plants.

Because of constant new growth, take great care of brand new plants with shaggy leaves. In some cases, plants develop dead zones, allowing Powdery Mildew to grow.

Make sure there is enough room amongst plants at all times. By stem cutting several of the plant leaves, you will greatly reduce the places where Powdery Mildew settles. Selecting leaves that are obscured from the sun also opens up plant resources, allowing you to improve your production.

Powdery Mildew Treatment in the Indoors

You can control Powdery Mildew with chemicals. One way to protect leaves is thorough spraying. Protective fungicides should be applied before the disease becomes active and reproduces. Before the plant’s bloom, chemical and environmental controls will help to maintain the disease rate low, in both terms of occurrence and severity.

An amount of Trifecta crop management super concentrates every 72 hours could be used to control Powdery mildew indoors. Until the powdery mildew is not under control, you should utilize two ounces per gallon. And, once a week, add one ounce for each gallon as a preventative measure. Ensure that the plants have enough ventilation and airflow.

If somehow the infestation is under control, completely disinfect the grow room to remove every mold spores which may have remained. Sodium bicarbonate and water mixture have a far higher pH than powdery mildew could tolerate. Another proven method is the Ozone generator. Make sure to ventilate when re-entering the room.

Powdery Mildew Treatment in the Outdoors

Powdery mildew can be treated effectively with Trifecta Crop Management for both outdoor and indoor settings. Until the powdery mildew has been under control, apply 2 ounces of Trifecta Crop management Super Concentrate every 72 hours. Use 1oz weekly per gallon with regular checks. You should acknowledge both the climate as well as humidity levels to maintain a successful application.

Remove all affected vegetation, such as leaves and stems, unless the harm is serious. If at all possible, toss all of that in the garbage or destroy it. Manure should not be used on any one of the infected plants since the wind may disperse the Powdery Mildew, causing the compost materials to become contaminated.

Powdery Mildew On Cannabis Plants: How to Prevent It?

1.    Maintain Proper Humidity And Temperature levels.

Temperatures around 60 to 72 degrees Celsius are ideal for powdery mildew growth. This is also the temperature range which cannabis plants prefer. Increasing the temperature to 74 to 75 degrees will help to prevent powdery mildew while hindering plant growth. To avoid the spread of mold spores, maintain humidity levels under 45 percent.

2.    Promote The Flow Of Air

Overcrowding is among the most common causes of powdery mildew infection. Plants that are crowded together produce more humidity as well as provide shade for each other. In addition, powdery mildew thrives in this type of setting. As a result, raising the distance among plants addresses these issues and prevents the growth of spores by enhanced plant contact.

3.    Use Air Purification To Kill Pathogens.

Air purifiers do little more than circulating the air; these even eliminate spores as well as other bacteria that are undetectable to a human eye. Mildew occurrences can be prevented with an advanced filtration device.

4.    Hydrogen Peroxide Can Be Used To Purify And Protect The Water.

Hydrogen peroxide can be used to purify and preserve all appliances in the growing environment, which involves thoroughly cleaning all of the waste and intakes ventilation systems. Following the completion of each growth period, certain steps must be taken.

5.    Overfertilisation Should Be Avoided.

Plants that have been over-fertilized can grow faster; however, new growth is much more susceptible to powdery mildew. To maintain the plants healthy, reduce the fertilization steps.

6.    Filter The Airflow With HEPA Filters Then Sterilize It.

Air must be filtered then sterilized at all times. Both for outdoor and indoor growing settings, HEPA filtration is required with all airflow.

Powdery mildew spores would not be able to penetrate the growing atmosphere because of the air filtering mechanism. Filtrations necessitate diligent upkeep. After the air has been filtered, sterilization is necessary.

Powdery Mildew Prevention Techniques

Although sulfur dust is active against a wide range of powdery mildews, it should never be used in hot climates. Copper-based pesticides, baking soda treatments, as well as neem oil are among several organic therapies that have shown to be successful. Planting disease-resistant types, propping plants to enhance air circulation, eliminating infected plant portions, and disinfecting infected planting tools can all help to avoid or slow the disease’s development.

Powdery Mildew reproduces both sexually and asexually throughout its whole lifespan. The asexual condition produces asexual spores or ascospores. Ascocarps, including asci as well as ascospores, are formed during the sexual stage. Historically, this condition was known as chasmothecia and perithecia. Ascocarps are very often necessary for powdery mildew to live without the need for a living host when both phases are present.

Final Thoughts

It might be too late to respond once white powder forms on the leaves and stems of cannabis plants. Powdery mildew is among the most prevalent and dangerous diseases which affect cannabis plants. While pesticides, as well as other procedures, can help to control the fungus infestation, they cannot always prevent it from spreading.

Therefore, it’s critical to concentrate on techniques to keep powdery mildew from growing on cannabis plants in the very first situation. Preventative measures will also save you money over the long term by avoiding costly fungal infections.