The entire flower turns brown and usually drops within 24 to 48 hours. Only the flowers of the plant are affected. This disease can be confused with several other problems that can damage camellia flower petals. Slight browning at the edges of the flower petals may be caused by sun or wind. Suspect a disease problem if the brown area rapidly spreads to the center of the flower.
Cold temperatures can also cause browning of the flowers.
Dark, brown veins in the petals distinguish flower blight from cold injury. Sanitation is the best control. Pull off and destroy all infected flowers. Rake up and remove all leaves, flowers and plant debris that have fallen to the ground. Replace the mulch under the plant.