Geranium
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
>
Leaves turn reddish
Cold Weather
>
Plant actually disappears
Deer
>
Small holes in unopened buds
Geranium Budworms
>
Buds dry up; drop off
High Humidity
>
Spindly plant growth
Low Light
>
Leaves patched or coated with white
Mildew (fungus)
>
Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible
Mite
>
Lower leaves have yellow edges
Needs Fertilizer
>
No blossoms
Overfeeding
>
Foliage turns yellow
Root Rot (fungus)
>
Black powdery sooty mold fungus forms on honeydew; plants may die
Sooty Mold
>
No blossoms
Too Much Sun
>
Buds dry up; drop off
Too Much Water
>
Weakened plants; yellow leaves; leaves discolored; covered with honeydew
Whiteflies
>