Camellia Plant Diseases & Spider Mites

Fungus

• A number of fungi attack camellias, causing diseases that at best are unsightly, and at worst, lethal. Glomerella singulata is a fungus that causes dieback and canker in camellias. The disease causes the leaves of affected branches to yellow and wilt and gray blotches to appear on the stems of the plant. Cankers form that girdle the stems, causing complete death. Use fungicides containing copper to control it, and plant camellias in well-drained, acidic soil. Ciborinea camelliae carries flower blight wherein the flowers rapidly turn brown and drop in two days or less. Control by getting rid of infected plant material and applying a soil drench containing terraclor fungicide during the cold months. Pytophthora cinnamomi causes root rot in camellias, and is evidenced by red or brown roots instead of healthy white ones. It also eliminates feeder roots, and the plant may lose vigor over a period of years or die suddenly. Prevention is the best treatment, by selecting varieties of camellia that are resistant to root rot.

Gall

• Camellia is subject to leaf gall, where a large white lumpy growth replaces one or several leaves on the plant. The shriveled leaf tip may remain visible at the top of the gall. The galls are large and unsightly, but do not harm the plant physically. The best control is to remove them by hand and dispose of them. The galls develop spores as they age, and are best eliminated prior to the fuzzy white spores appearing to keep from spreading the gall.

Virus

• Only one virus, camellia yellow mottle virus, is of much concern in camellias. Symptoms are irregular mottled leaf blotches that are bright yellow on otherwise healthy green leaves. In advanced cases, the entire leaf turns yellow, and the petals of flowers exhibit similar white blotches. The virus is transmitted through infected root stock and has no treatment.

Mites

• Tiny, eight-legged bugs called mites sometimes afflict camellias. The two-spotted mite, the tea mite and the southern red spider mite all have piercing mouthparts with which to suck the sap out of the plant. Spider mites usually appear as bright red dots. Evidence of the mites is a bronzed or silvered appearance on plant leaves caused by speckling where the mites have fed. Treatment with an approved acaracide is the best method of treatment to bring the tiny pests under control.