Camellia Leaf Gall
Camellias are relatively unfussy and problem-free shrubs, but they can develop camellia leaf gall, a unique and odd-looking disease. Here’s how to identify and treat it.
Symptoms are a fleshy thickening of the leaf, sometimes with a distinct “orange peel” texture. The affected leaves are also pale green in color, occasionally blushed with pink. It’s usually seen on new growth in spring, more commonly on Camellia sasanqua than C. japonica varieties. Affected leaves stand out like a sore thumb and ID is pretty easy.
Camellia leaf gall is caused by the fungus Exobasidium camillae, and only affects camellias, so there is no concern with it spreading to other landscape plants. If left alone, eventually the thickened leaf will rupture and whitish fungal spores will be released. Eventually the entire leaf becomes hardened and brown.
Treatment is simple-prune off and dispose of the affected growth in the trash (in a closed plastic bag to avoid spreading the disease) as soon as you notice it. Do not compost infected leaves. The rest of the plant will not require treatment as the infection is contained to the affected leaves. To avoid infection, always rake up fallen leaves, and try to keep foliage dry.
Preventive fungicides applied at bud break can prevent camellia leaf gall, but the disease is so low-impact and easy to treat that the time and expense is usually unwarranted unless there is a history of extensive infection.
Don't panic, there are a few common (and benign) reasons that trees drop leaves in summer.