There are many diseases and other ailments that can affect cannabis plants. Most growers only encounter a small portion of these issues.[1]

Mold & fungus

Root rot

If roots are exposed to too high humidity they can begin to rot and become damaged.

Powdery mildew

Grey Mold (Bud rot)

Nutrient problems

Nitrogen toxicity

Too much nitrogen will result in deep green leaves. The apex of the fan leaves can also "claw" downwards.

Pests

Spider mites



References