A bigger challenge is deducing the source of trouble when many explanations are possible. Leaf yellowing and wilting, for example, may be due to insects, nematodes, diseases, or improper watering.
If you can’t find clear evidence of a pest, the best course is to assume that growing conditions are at fault, then to focus on improving them. If you're convinced a pest or disease is the villain, check the rogues’ gallery for a likely candidate— but be sure all the evidence fits before placing blame.
For help in solving problems you can’t identify on your own, consult your Cooperative Extension office or a reputable local nursery.
Types of Bugs
Insect Damage Charts
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