Viral Disease

• Yellow mottle leaf virus is a slow developing virus that only affects camellias. The first sign of yellow mottle leaf virus is yellowing of leaves and a pattern of mottled green and yellow on the leaves. This virus is usually tolerated well by the camellia, because the virus has little or no effect on flowering, but it does weaken the plant. At the present time, there is no known cure for this disease.
  
  

Fungal Diseases

• Petal blight is a rapidly spreading disease. Symptoms include brown spots in the center of the petal, moving to the entire bloom, and eventually dropping off.
  Canker causes branches to wilt and bark to split away from the camellia, leading to pinkish cankers. Shoots may begin to die back.
  Root rot is a soil-borne disease. Signs of root rot are yellowing and limpness of leaves and stunted growth. Flower buds may fall to the ground before opening.
  Leaf gall distorts the leaves of camellias severely, enlarging and thickening them abnormally.
  
  

Causes

• Major cause of disease, such as root rot, leaf gall and petal blight is excessive moisture or lack of drainage. The fungus that causes root rot can be spread by the flow of water and the movement of soil. Canker is caused by dry periods. Other common causes of diseases of the camellia are: compacted soil, deficiencies and imbalance of nutrients, persistent insect invasion and transplant shock.
  
  

Prevention/Solution

• The best way to prevent disease is to simply keep the area clean around the camellia. Pull off infected flowers and dispose of them. An application of fungicide every two weeks will be necessary. Prune and destroy affected twigs and branches. If the camellia has leaf gall, cut off affected leaves and remove galls and burn them.
  Water the camellia consistently, but make sure you don't over-water. Slightly cultivate soil around the camellia to prevent compaction. Get rid of insects by spraying a pesticide every two weeks. Recheck your fertilizer label to see that it has all the nutrients that a camellia needs.
  
  

Time Frame

• Root rot is the most damaging disease to a camellia. It is highly possible that even the healthiest of camellias affected with root rot can wilt and die in just a matter of a few days.
  Within 24 hours of infection with petal blight, flower petals begin to turn brown. Only after a couple of days, the flower petal will fall to the ground.
  It is possible for a camellia to stay dormant for five years. Consistent spraying of fungicides on a biweekly basis will rid camellias of most diseases in two months or less.
  
  

Warning

• Do not add diseased leaves, diseased petals or diseased branches to your compost pile. This will spread diseases to other plants. Always disinfect garden tools with alcohol after each use to prevent spreading disease to other plants in your garden.