Camellia Leaf Problems

The brownish black areas on the leaves of the plant were caused by excess direct
sunlight. These areas turn yellow at first, then gradually darken as the tissue
dies. Often the dead tissue is then infected by secondary fungal pathogens.
Japonica and reticulata camellias are more susceptible than sasanquas, so they
are best planted in sheltered positions with protection from the hot midday sun.

Yellow leaves can indicate that a plant is suffering from a nutrient deficiency
or is affected by cold weather, but yellow blotches on camellia leaves are often
caused by a virus. Normally only a few leaves show symptoms, which can range
from a few spots to almost the whole leaf being yellow. This unnamed virus is
associated with marbled flower colours, and camellia breeders sometimes
deliberately infect plants to achieve particular colour combinations in the
flowers. Control measures are not necessary, as the overall vigour of the plant
is not affected. The virus cannot be cured but if you wish you can simply trim
off any shoots which have yellow leaves.