Camellias are evergreen shrub or small trees that grow up to 20 m high. There are 100 to 300 camellia species and around 3,000 hybrids found growing in eastern and southern Asia, from the Himalayas east to Japan and Indonesia. The ornamental species C.japonica, C.sasanqua and their hybrids are the source of hundreds of cultivars widely planted in the UK and Ireland. Flower colour ranges from white through pink to red.
Culture for Camellia
Most species of camellia grow well in acid soils rich in humus. Growth on alkaline i.e. chalky or calcium rich soils will be poor. Likewise, most species of camellias require a large amount of water, either from natural rainfall or irrigation. Camellia plants are recognized as drought sensitive so extra watering will be required in periods of drought. Camellia thrive in part shade but will tolerate full sun once established.
Concerns about Camellia
In general a relatively pest free plant. Camellia gall is a fungal disease causing large cream coloured swellings (galls) but little or no long term damage to the plant. Camellia flower blight is a disease caused by the fungus Ciborinia camelliae. Brown flecks on any part of the petal, rapidly spread to form a brown blotch that eventually kills the flower.
Management Practices for Camellia
Sample soils for nutrient and pH levels. Nitrogen, magnesium and potassium deficiencies are common. Aim for a pH of 4.5 to 5.5 for optimal growth. Keep plants well watered especially in times of drought. Treat foliage preventatively with fungicide sprays for galls or flower blight if conducive weather conditions occur.