Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Swollen bumps on stems
Canker (fungus)
Young leaves; discolor and fall
Honeysuckle Leaf Blight
Leaves covered with white powdery substance
Powdery Mildew
Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible; sometimes galls form on leaves
Spider Mites