Prised for their shiny evergreen leaves and winter blooms, Camellias have long been a favourite of southern gardeners. When given the proper growing conditions, these shrubs are typically hardy and carefree. However, problems can occur even under the best conditions. To avoid most problems, plant your Camellia in well-drained, acidic soil. If you have done this and problems persist, it is important to identify and treat symptoms before they get out of control.
This disease typically enters the plant through a wound such as a pruning cut or lawnmower ding. It causes the leaves to yellow and wilt and creates grey blotches on the bark that sometimes become oozing cankers. Sanitation is the best defence. Prune diseased branches 6 inches below the lowest sign of disease. Disinfect the pruning tool between cuts with a water and bleach solution.
If your Camellia's flowers turn brown and drop within 24 to 48 hours, it has flower blight. To control this disease, remove and destroy affected flowers and plant debris. Soil drenches and foliar fungicide sprays help lessen the effects of flower blight.
This fungal disease causes leaf yellowing, sluggish growth and wilting. It turns white, healthy roots a reddish brown colour and eventually kills the plant. Root rot is difficult to control, so it is best to avoid the problem altogether. One solution is to plant Camellia sasanqua and Camellia oleifera varieties, as they are more resistant to root rot than Camellia japonica. It also helps to plant your Camellia in well-drained soil.
Leaf gall is a fungal disease that typically occurs with new spring growth. Signs of leaf gall are fleshy, thick leaves with galls on their undersides. The best defence is to remove the leaves before the galls rupture and turn brown. Try not to wet the leaves when watering as galls thrive in humid, moist, shady conditions.
Fluctuations in moisture and temperature are the main reasons for bud drop. Other reasons include poor soil, insufficient drainage and Camellia bud mites. If this problem persists year after year, try transplanting your Camellia in a more suitable location.