How to Kill Powdery Mildew on Clones

Separate the plant clones from one another, if possible. A plant clone can grow from a single stem, usually very close to the original. But unfortunately the close proximity of plants causes poor air circulation between the leaves, and can block sunlight from properly reaching each plant. As a result, uproot your plants and space them out if you have a crowding problem.

Increase your plant's access to sunlight. If one or more of your clones rests in a shaded region, powdery mildew can run rampant because the plants are already in a weakened state. Plants grow as a result of photosynthesis, and photosynthesis requires sunlight. Deprive your plants of sunlight and they become vulnerable to an array of diseases.

Remove the affected leaves from the clones. To properly control powdery mildew, you must make an ongoing daily effort to examine your leaves and look for signs of the fungus. When a leaf shows visible white patches of powdery mildew, remove it at once to prevent mildew from spreading.

Apply a fungicide to your clones about once every 14 days. Start with a natural oil based fungicide, such as neem oil, which can kill the fungus using the least harmful ingredients. Apply the fungicide from a spray bottle or garden sprayer.

Apply a stronger fungicide if the first fungicide yields no results. Some heavy strains of powdery mildew will require something a bit stronger than natural oils, such as biological or sulfur-based fungicides. Apply biological and sulfur fungicides only as a last result, no more than once every 14 days.