4 Telltale Signs of Mildew on Cannabis Plants

One of the biggest antagonists to growers is mildew. Plants stuck in environments with high humidity and still air are likely to develop the fungus. If you want to learn how to better care for your cannabis plants, start by understanding the four telltale signs of mildew.

Yellow or White Powdery Substances

One of the most identifiable signs of mildew is the presence of a yellow or white powdery substance on the surface of your cannabis plants. This growth is primarily present on the leaves, but it may also spread to the stems and buds.

Powdery mildew is a parasitic fungus that depends on the living tissues of the host plant for its survival and growth. If not controlled, it can cause substantial harm to the plant. This fungus exhibits a destructive behavior and spreads irregularly, setting it apart from the beneficial trichomes.

Moldy or Musty Smells

Do you detect a strange moldy or musty odor in your grow room? Mildew is the likely culprit.

The distinctive smell is a byproduct of the fungus’s metabolism; it intensifies as the infection worsens.

Early recognition of this smell is crucial for preventing further spread of mildew. This odor can serve as a warning that even though the visible signs of mildew may not yet be apparent, conditions are ripe for its growth.

Discolored or Spotted Leaves

As the mildew infection progresses, you’ll notice that your cannabis leaves start to develop discolored patches or spots. Typically, these spots will be yellow, brown, or purple with brittle leaves.

These discolorations are not a direct result of the fungus itself but rather the plant’s response to the infection through hypoxia. Hypoxia refers to a lack of oxygen and causes the plant to form discolored areas as it struggles to fight off the mildew infection. If you see these imperfections on cannabis leaves, it’s clear that the plants are experiencing stress due to mildew.

Fuzzy or Cotton-Like Growth

When mildew takes hold, patches of fuzz or cottony spots grow on your plants. The spores can disperse through the air and infect the entire crop within a matter of days. The sooner you eliminate these visible signs, the greater the likelihood of salvaging your plants.

How To Prevent Mildew Growth

Preventing mildew growth is much easier than treating one of the telltale signs on cannabis plants. Read on to explore tips you’ll need to prevent this fungus from thriving in your grow room.

Balance Ventilation and the Humidity Levels

Stagnant air and high humidity cultivate an environment where mildew thrives. A ventilation system with fans that constantly circulate the air is a must. Additionally, humidity levels should linger between 45 and 60 percent for ideal conditions.

The AC Infinity climate control system is an incredible tool that allows you to customize both temperature and humidity. When paired with a high-quality ventilation system, this AC system ensures mildew will be a problem of the past.

Avoid Overcrowding

Crowded plants can trap moisture, creating localized areas of high humidity. Proper spacing between plants allows for better airflow and can greatly reduce the risk of mildew.

Provide Plants With Proper Nutrients

Just as a healthy immune system can protect you from illness, healthy cannabis plants are more resistant to mildew. Feed your plants a balanced and complete nutrient regimen to keep them strong!