Camellia flower blight is a potentially deadly disease that will turn flowers brown. The disease begins in early spring, particularly in moist weather conditions. In early stages, camellia flower blight starts as small, brown spots. The spots grow over time to cover the flowers. The flower will die in 24 to 48 hours. Remove all flowers that have been affected by camellia flower blight, and dispose of them immediately. The blight is caused by a fungus in the soil, so clean away all mulch and debris around the plant.
Camellia flower blight is one of the quickest and most deadly fungal diseases but not the only one that will turn flowers and foliage brown. Early root rot turns flowers yellow before the entire camellia plant begins to brown and wilt. Root rot may cause the plant to die quickly if it is not treated. Root rot fungus develops in soil where drainage is poor. Leaf gall often occurs in early spring when new growth appears on camellia plants. Young, new leaves will become distorted and turn pinkish or whitish in color. Later, the abnormal areas of the leaves rupture and leave behind white spores that harden and become brown. Leaf gall creates no significant damage but does discolor the plant. Remove all areas of the plant affected by leaf gall, remove all fallen leaves around the plant and destroy it all.
Tiny scales feed on camellia foliage, sucking the nutrients right out of the leaves. Heavy feeding will weaken the plants and create wilting of the leaves and flowers. Tea scale is particularly damaging to camellia. Early symptoms appear as yellow blotched on leaves. Remove all foliage affected by scales by hand, and treat the plant with pesticide.
When flower buds turn brown and drop prematurely from the camellia plant, bud drop is the culprit. Extreme weather changes may lead to bud drop. Plant camellias in an area where they will not be too wet or too dry, and protect the plants from freezing weather. Plant camellias in partial shade to protect them from very hot sunlight in the summertime. Bud drop may also be caused by poor soil drainage or a lack of nutrients in soil. Bright sunlight may also cause sunscald, which is something like a sunburn on the plant. Leaves and flowers may appear bronzed or burnt when sunscald occurs.