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Growing Camellias in Southern California
By Dorothy Carroll
Camellia sasanqua unknown variety
Photo: Lucy Warren
One of San Diego’s winter blooming "stars" in the garden is the camellia. The genus Camellia includes about 80 species, of which several are used as ornamental plants (a couple are used commercially). These leathery-leaved evergreen flowering trees and shrubs are native to southern and eastern Asia, and have been cultivated in China, Japan and Korea for centuries. They are easy to grow in Southern California with a little extra care, some shade and plenty of organic mulch.
The camellia was named for Georg Josef Kamel (1661-1706), a Jesuit pharmacist born in Bruno, Moravia who botanized from 1688 onwards in Luzon in the Philippines. In 1704, he wrote an account of the plants under his Latinized name, Camellus. In his reference works, Linneaus also named the flower for Georg Josef Kamel by changing the "k" to a "c" to fit the Latin alphabet, which has no "k."
The camellia made its first appearance in England when sent by James Cunningham, the only survivor of the massacre of East India Tea Company officials in 1705. It seems, however, that Lord Petre—then called "the best botanist in England"—actually killed the lone camellia when he tried to grow it in a greenhouse that was too hot. Fortunately, his gardener James Gordon, had taken cuttings of the camellia, which survived.
The camellia arrived in America in the late 18th century and has been admired and propagated here for over 200 years. According to E. C. (Gene) Snooks, President of the San Diego Camellia Society, "the camellias first entered the United States in New Jersey. However, they soon became so popular and so much a part of the Southern gardens that they were almost considered a 'native' in the South." The frost-free climate, ample rain and slightly acidic soil proved an ideal environment for naturalization.
Commercial Camellia Products
Camellia sinensis was treasured for centuries in China, long before it was ever brought west. It is the source of dried leaves for tea, and as such is the most commercially viable species of camellia. Grown here occasionally as an ornamental plant, its flowers may be white or pink, and it's dense, glossy dark green evergreen foliage can be a useful ornamental hedge plant. Left on its own, it may grow to a height of 50 feet. Tea oil is another camellia product crushed from the seeds. Tea oil is harvested principally from
C. sinensis and C. oleifera.
Most of the camellias grown in America come from three distinct species: C. japonica, C. sasanqua and C. reticulata.
C. japonica is the most popular, and presents a wide variety of colors: red, white, pink and yellow, as well as variegated blossoms. Bloom-time is late winter and early spring. They are easy to grow in shade and semi-shade. The roots are not invasive, so they're well suited to group plantings with other plants and are an ideal foundation shrub. Leaves are a glossy bright green and the plants produce four-inch flowers. For a short period of time, C. japonica will tolerate temperatures down to 10 degrees F; conversely, foliage will scorch if it's too hot and dry.
Plant C. japonica four to eight feet apart where they receive no direct sun after 11 a.m. Water consistently and never let the soil completely dry out. After about two years in the ground, C. japonica will be established and will tolerate dryer conditions. Try to find a happy medium—not too wet, and not too dry—and your Camellia japonica will thrive. Prune only when it gets overgrown.
Occasional bud drop may be the result of unfavorable temperatures, stress of inconsistent moisture, malnutrition, frost, mites or even root rot. None of these are common problems with camellias, however, and a regular schedule of feeding and watering usually will prevent or eliminate the problem.
Camellia sasanqua, originally from southern Japan, is the hardiest of the species. They bloom from fall to early spring, and will tolerate temperatures to 0 degrees F. They are the most sun-tolerant of the camellias and can survive hot, dry climate, though they thrive in the shade. Their flowers are smaller than C. japonica, averaging only three inches in diameter. They make up for this by being more prolific bloomers than C. japonicas or C. reticulata. Colors are from white to pink to light red and variegated. They come in single, semi-double and double forms. Best of all, they are fragrant.
C. sasanqua is a bush form of easy-maintenance shrubs growing to about three feet high by four feet wide. Grow them in the ground, in containers as patio trees, in hanging baskets or as low spreading shrubs. The sasanquas have numerous blooms all up and down the stem and have lots of color. If you’d like a beautiful and colorful display, you can also espalier C. sasanqua against a wall or fence. They require very little care.
According to Gene Snooks, C. reticulata is a newer species, introduced from China around 1957. They have larger, more open blooms but the plants are very "leggy." Hybrids are specified as reticulata if they are a reticulata cross.
Camellia flowers are described by their form and each is distinctive. Single has one row of petals surrounding a center cluster of well-exposed stamens. Semi-double has two or more layers of petals. Camellia semi-doubles are broken down into the Anemone and the Peony forms. Anemone has a mass in the middle consisting of petaloids (small clustered petals) and stamens mixed together. In the Peony form, the center stands higher and contains the mix of stamens and petals. The Rose-Double form has many layers of regular and overlapping petals and shows small stamens in the middle when fully open. The Formal Double form is similar except it never shows stamens.
In addition to purchasing camellias through quality local nurseries, there are three ways new plants are produced:
1) Grafting scions, or small sections, of the parent onto another rootstock results in plants identical to the parent.
2) Seeds produce plants which have varied characteristics, even if from the same parents.
3) Sports are wayward offshoots from the parent with different characteristics on that section of the plant, such as color or foliage. These are usually grafted to produce additional plants. Gene Snooks grows a lot of his camellias in pots. The following are his personal opinions on the care and culture of camellias, backed by many years of success. By growing in pots you have better control of the water and fertilizer. Never let them dry out completely. The plant may come back once, but if it dries out more than once, you'll probably lose the plant.
Camellias prefer loose soil, high in organics. To plant them in the ground, dig a hole two times the diameter and two times as deep as the root system of the plant. Use agricultural gypsum to break down the soil in the ground. Mr. Snooks recommends three handfuls mixed with the soil fill dirt. He adds, "I like to use one-half regular soil and one-half redwood compost. I prefer the redwood compost to peat moss."
Plant with the soil of the root ball mounded two inches above the ground level and mulch with pine needles or redwood chips. This forces the roots down into the ground instead of encouraging them to move up seeking the sun.
If you keep your camellias in containers, transplant them incrementally as they grow. Don’t go from a one gallon pot to a five gallon pot right away or you’ll lose your plant. It takes time to move up from one pot size to another. Go from a one-gallon to a two-gallon, then next time from a two to a three-gallon, and so forth.
Mr. Snooks strongly recommends not using commercial fertilizers on camellias. "Tell them to use nothing but cottonseed meal on their camellia plants. Some growers use five percent blood meal, but blood meal is 'hotter' and unless you’re very careful and know what you’re doing, you can burn your plant and kill it. Stick with the cottonseed meal, available at most good nurseries."
For best success, apply the cottonseed meal three times a year. Good target dates are St. Patrick's Day, Memorial Day and the Fourth of July. Use a couple tablespoons per gallon of pot size. You cannot kill your camellia plant with cottonseed meal, but more is not necessarily better.
Regular watering, especially using pot culture, is critical. Mr. Snooks strongly emphasizes that growers, "never, never let your plant dry out." Be consistent when watering. You can check the need for water by lifting the pot. If it feels heavy, the soil probably has enough water. If the pot feels light, it probably needs water. Keep your plants evenly moist—not wet. If the plant seems root bound, you can use a fork to loosen the roots a bit. Again, he stressed the importance that you never let your plant dry out or "you'll pay the consequences with lost blooms and perhaps a lost plant that year."
Those with camellias planted in the garden should observe these guidelines, as well. In ground plants have stronger and more extensive root systems, but still need regular water, regular fertilizer and benefit from a layer of mulch.
Pests and Diseases
Camellias are not very susceptible to insects and diseases. However, the major disease is petal blight. Petal blight is caused by a one to two inch mushroom that puts out thousands of spores. The spores splash on the camellia plants in the winter rains causing bud rot and, if the buds open at all, the petals to decay to a brown and mushy texture. Blooms fall on the ground and if they are not picked up right away they host more spores. The spores on the ground form sclerotia that can stay dormant for up to five years.Then when the weather is right—cool and wet—the mushroom develops, sends out its spores and the cycle repeats.
"There's no cure for petal blight," said Mr. Snooks. "The only way to help control it is to remove any blighted blooms and pick them up right away as they fall off your plants before they rot." Last year, he picked up 8,834 blooms off the ground at his home—an actual journal count. Also, remove all mulch annually and replace it with fresh material.
It is important never to throw the blooms and old mulch into your 'green' trash. Pick them up, put them in a plastic bag, seal it and put it in your regular garbage. Encourage your neighbors do the same thing. Removing and destroying the damaged blooms to the main landfill prevents the spores from recycling back through compost to recur in your yard or anyone elses.
Petal blight will not destroy camellia plants, the damage is only unsightly and undeveloped blossoms. After all, you grow the plants for their beautiful bloom, and petal blight can ruin some to all of the blossoms on the plant.
An alternative preventive measure is to cover the soil with a 6"-12" deep bed of pine needles or redwood bark. The mushroom spores that cause the petal blight will not normally penetrate such a deep layer. Ask your neighbors if you can bag up pine needles from under their pine trees if you don’t have any. They'll probably be happy to get rid of the pine needles and your camellias will definitely benefit.
As for other pests, "in spring, it's looper worms. They eat the new, soft camellia growth," said Mr. Snooks. "A sharp eye, a squish and you shouldn't have much problem with looper worms after that. Occasionally mites get into the plants, but they don't seem to be much of a problem. You'll rarely get scale on camellias in San Diego."
• Buy Camellia plants while in bloom. Select plants with a moderate number of buds. Plants with too many bloom buds are expending too much energy.
• Look for live growth buds (pointed shaped buds) versus bloom buds (fat, round buds) near the base of leaves. These will produce next year’s blooms.
• Disbud. Pinch off all but one bloom bud per stem end for larger, more evenly shaped blooms. Multiple buds have the share the plant energy and are smaller.
• Buds that drop before they open are a result of: a) irregular, inconsistent watering. b) variety—some tend to drop their blooms before they open, especially C. 'Elegans'.
• Increase shade by using 50 percent shade cloth overhead. Informal experiments suggest red shade cloth enhances camellias.
Reprint from January/February 2008, Volume 99, Number 1
Mission: To promote the knowledge and appreciation of horticulture and floriculture in the San Diego region.