Downy mildew is sometimes called false mildew and affects vegetative as well as flowering cannabis plants. Powdery mildew occurs when temperatures are below 76° F (26° C) and it appears as a whitish-yellow spot on top of leaves, creating pale patches on leaves.
This can spread very quickly by causing plant growth to slow down, leaves to die off and can be fatal for cannabis plants. Do not promote disease by crowding plants too closely together in your garden, but sure to keep some space between them.
Cleanliness is the best for preventative measures so always use sterile growing mediums and do not re-use them. For further infection, you will need to remove all leaves that are infected and throw them away.
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