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White Powdery Mildew

White Powdery Mildew is a fungal disease that appears on the leaves and stems. Mildew grows where the light won't reach, and moisture levels are high, like leaves resting on top of each other. It's airborne, spreads from plant to plant and presents as a white powder-like substance. Remove any affected bud sites as the cannabis won't be safe to consume. When starting plants, ensure there is enough space between all the plants to lower risk.

Can be caused by:
• Poor airflow
• No ventilation
• Leaf on leaf contact
• Extended periods of rain (outdoors)
• Temperature & Humidity (VPD) fluctuation
• More susceptible when nutrient deficiencies occur
• Transferred from a infected plant

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Affected leaves should be removed from the plant immediately. Clear bigger fan leaves, and trim in high-density, bushy areas.
If indoors, install a dehumidifier and set it to correct humidity levels for the plant's life stage. Keeping temperatures above 80*F will also help kill off White Powdery Mildew.

Homemade Sprays:
Before using any sprays indoors, turn off all fans.

• Potassium bicarbonate: 1 teaspoon per gallon of water.
• Milk: 1 part milk to 3 or 4 parts water.
• H2O2: 1 part 3% H2O2 to 3 parts water.
• Baking soda: 1 teaspoon per gallon of water.

• Docton Zymes Eliminator
• Sulphur based fungicides
Do not spray on buds; sprays are usually not safe to consume.

Plant washes like Lost Cost should also clear powdery mildew from the leaves.

If powdery mildew is found on buds upon harvest, we really don't recommend consuming it, but if you must, be sure to wash your buds first.