Keeping Your Camellia Pest Free

red camellia (Camellia japonica)

red camellia (Camellia japonica)

Q: I have a camellia growing under the eaves near my front door with a northeast exposure which gets no direct sun during the winter. The problem is that it gets many flower buds that form fully but most either fall off before opening or soon after opening fully. The petals are brown inside the bud at the stem end, and the outer petals are also brownish. The plant is otherwise vigorous. Any ideas on how to fix this problem? –Richard Olmsted, Simi Valley
A: Your plant is suffering from two common camellia conditions, one pathological and the other physiological. Brown camellia petals point to the activity of a fungus known as Sclerotinia. The condition is called petal blight, whose symptoms are brown spots on flower petals. Sclerotinia fungus takes hold as a result of excessive watering, poor air circulation, or heavy soil. Overhead irrigation of camellias, in depositing water on leaf, stem, bud and flower surfaces, should be avoided.
When the infected buds drop to the ground, Sclerotinia fungus spores lie dormant until the following year when, in response to moisture and the presence of new buds, they infect the plant all over again. To control the blight, pick brown buds off the plant before they fall. Alternatively, a fungicide applied to the soil just as buds begin to swell will prevent germination of fungal spores on petals.
The most frustrating phenomenon to be seen on camellias is not the result of a disease but of a physiological disorder. This condition, known as bud drop, is characterized by the falling of unopened or partially opened flower buds. Several conditions, some of them at opposite ends of the cultural spectrum, have been implicated in the occurrence of bud drop: dry soil, overly wet soil, freezing winter temperatures, excessively warm winter temperatures and inadequate light exposure.
In the Valley, camellias do best in a partial sun/light shade exposure. One of the best places in the world to learn about the light and shade requirements of the camellia is at an arboretum right in our own backyard. Descanso Gardens, in La Canada, has one of the most outstanding collections of camellias found anywhere on the globe. February and March are the months in which the Descanso camellias are at their most glorious. When you look at the camellias there, you will appreciate their specimen qualities. Left to grow to their full height and minimally pruned, arboretum camellias have a treelike quality that is seldom seen in neighborhood landscapes. Here’s a thought to conserve water: Turn your back yard into a camellia forest.
With their plush, multilayered flowers of white, pink or red, camellias could easily be mistaken for winter roses. There is a major difference between camellias and roses, however, and it’s in the relatively minimal maintenance that camellias require.
I have observed camellias 8 or 10 feet tall, covered with flowers from top to bottom, that have never been fertilized and are watered only occasionally with a hose. I am acquainted with a camellia shrub that has lived in a state of benign neglect for more than two decades and yet, come February, each flower emerges without blemish, as though it were crafted of porcelain or silk.
Because of their preference for shade and acid soil, camellias are often grouped with azaleas and hydrangeas. But camellias deserve to stand alone, both in terms of their care and for the weight they carry as landscaping subjects.
Where watering is concerned, established camellias could almost be described as drought tolerant. Properly mulched, established camellias should not need to be watered, even during the summer, more than twice a month. Newly planted camellias, on the other hand, will require weekly deep soaking during their first year or two in the garden.
There is a wonderful Web site at www.sazanka.org for viewing scores of gorgeous camellia varieties, many of them grown locally at the world famous Nuccio’s Nursery in Altadena.
TIP OF THE WEEK: Terri Taylor of Van Nuys propagates her plumerias each year at this time. She take 12- to 18-inch terminal stem pieces and sinks them around 5 inches deep into fast-draining soil, both in pots and in the ground. Plumeria, the Hawaiian plant with the mellifluous, pinwheel flowers in pink, yellow, red or rainbow colors, is as easy to grow as any cactus and just as water thrifty.

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