A member of the tea family, Theaceae, Camellia japonica is one of Japan’s most famous flowering trees. Known as tsubaki in Japanese, this plant is a common small tree throughout the warmer regions of the Japanese archipelago. In recent times it has been widely cultivated as a garden plant, but in the not so distant past the oil derived from its bulbous fruits was used as a multipurpose product, serving as a food, a hair and skin treatment, as well as a machine oil.
Camellia japonica in nature is an evergreen subcanopy tree, commonly 3 to 6 meters tall, with occasional specimens being quite a bit higher than that. The tallest on record is 18 meters (that’s almost 60 feet!). I’ve seen many in the 10-12 meter range with trunk diameters approaching 60 centimeters in really large trees. The bark is an even gray color and very smooth.
The wide, slightly serrated ovate leaves are borne in an alternating pattern and typically measure between 5-10 centimeters long and 3-6 centimeters wide, ending in a pointed tip. They usually are a deep green color on their dorsal surface and a bit lighter underneath. The dorsal surface is also very glossy, adding to the visual appeal of this plant. The soft, new leaves are most actively in growth after flowering in the spring. Flower buds are formed in the fall and over winter until opening in late winter or early spring.
The flower petals of wild plants are typically deep red, though pure white forms have been reported. They are joined at their bases such that when the flower falls off, it is intact (we’ll see why that is important later). The prominent cluster of stamens are a yellow orange color while the three lobed pistal is “lost’ in them. Wild flowering types commonly boast only a handful of broad petals and the blossoms tend to remain rather cupped compared to many of the cultivated varieties. The fruits are nearly perfectly round before opening, starting out apple green and maturing into a purple-red. They open in three sections (called locules), each containing anywhere from 1-2 large brown seeds.
Flowering season in southern Japan starts in winter, usually not before January, peaks around March, and trails off in late April. At higher elevations flowers can persist even into mid May. Flowering is later further north, and can last into mid spring, however, it is not uncommon to see this tree in flower when snow is still falling. This cold weather flowering habit has earned it one common name, rose of winter. Due to the relative lack of insects in winter, the flowers are often pollinated by small birds, in particular the Japanese white-eye, Zosterops japonica.
Tsubaki is a common denizen of the evergreen broadleaf forests of southern Japan and northward even into the warmer coastal reaches of northern Honshu’s Tohoku region. It is absent from Hokkaido (as a native), but is found in virtually all the islands of Japan right down to Okinawa and beyond to Taiwan, as well as parts of mainland China and South Korea. Along with two other Japanese trees, Japanese laurel (Aucuba japonica) and Neolitsea sericea, this plant is a dominate understory tree in these largely evergreen forests, so much so that this forest type is called yabutsubaki kurasu iki (translating as “wild Camellia japonica class region” forest type).
At least two recognized naturally occurring variants exist – one in the north end of its range, and the other in the south. The northern plant is found in a unique habitat for this species – on the Sea of Japan side of the northern part of Honshu in Japanese beech (Fagus crenata) dominated, deciduous forests that experience long, cold winters with heavy snowfall. This variety has been given various names including C. rusticana, C. japonica v. rusticana, C. japonica v. decumbens, and C. japonica subsp. rusticana. In Japanese it is called yukitsubaki, meaning “snow Camellia” – also its common name in English. This plant has proven to be much more cold and snow resistant than more southern varieties. In form it looks much like the common wild type, but is smaller in stature, usually not standing more than 2 meters tall.
The other natural variant is the variety macrocarpa. It has very large fruits, up to three times the size of a typical one. Although each fruit is much larger, the seeds within are not, but they are more numerous. A common variety fruit might contain 2-4 seeds while this variety’s fruit typically has 6 or more seeds in each. Other than that, the tree is nearly indistinguishable from the common type. It is found only in the islands south of mainland Kyushu, from Yakushima to Okinawa. Because of the large fruits the potential for oil production with this variety is high. The large fruits have earned it the nickname “apple Camellia” since the fruits are nearly apple sized.
In my local area C. japonica is a very common forest tree, found from sea level to a 1000 meters elevation. It is most commonly seen in small groups as a understory tree, but occasionally grows on ridge lines in full sun. It seems to reach is greatest stature along water courses in protected valleys – in such places it becomes truly tree sized, up to 10 or more meters high with a trunk as thick around as your thigh. It is a great joy to see a large specimen in full flower on a late winter day.
Camellia japonica is a culturally significant tree in Japan. It has been the focus of a number of rituals and beliefs, as well as an important source of raw materials, most notably Camellia oil. Long before its exportation to Europe, this plant was admired by the Japanese people with the first special varieties having been developed and written about during the Edo Period (1600-1868). At that time it was custom to plant a special camellia on the grave of a departed loved one, however with the advent of the Meiji Period, such traditions were largely lost.
Check out this video of both the wild type and various cultivated forms in Japan:
As noted above, the flowers of this tree fall intact, such that the ground beneath can become literally covered with their blossoms. This is called ochitsubaki in Japanese, and literally means “fallen tsubaki“. During the Edo Period samurai did not allow tsubaki to be planted at their homes because the common practice in those days was for them to behead outlaws. The fallen Camellia flower represented this act, and a negative attachment was placed on the plant by them. Commoners had no customs about this plant however. Interestingly, this idea has lived on in the custom of it being taboo to visit people in the hospital with neck injuries since the fallen flower represents a severed neck. At another less sinister level, ochitsubaki has been a popular topic for many haiku poets.
Camellia oil (also known as tea oil and tsubaki oil) was the focus of a fairly concentrated industry surrounding this plant for centuries. At it peak in the early 1900s, this tree was planted and the seed collected to extract its precious oil. It has been used in soaps, in hair oil, lubricants and paints, and remarkably is even edible. To this day, sumo wrestlers use it to keep their hair in place, and it is used to fry tempura since it makes the batter more light in texture. It is also used in salad dressings, marinades, and sauces. Traditionally, camellia oil was used to keep swords, axes, and other metal instruments from rusting. It also was formerly used as a light fuel oil.
The wood of tsubaki is valued, but due to the tree’s relatively small size, it is difficult to get boards out of it. Both its charcoal and wood ash have been important historically. In sake brewing, wood ash is needed, and Camellia wood ash is considered the highest quality.
Camellia japonica prefers a moist, acid soil with at least some shading during the hottest part of the day. Having said that, they are quite tolerant of heat stress and sunshine as long as the roots are not subject to doughty conditions. Growth is slow, so don’t expect a forest tree quickly. Luckily, plants flower at small sizes and can be container grown for years, though they do better when planted out. They also respond well to pruning, which can be done anytime during their growth cycle, from late spring until late summer. Avoid pruning in fall to allow the flower buds to form.
Most cultivated forms today are highly selected and bred varieties with multiple petals, blotched and variegated flowers, and so on. Interestingly, the wild form is valued in Japan nearly as much as the fancier varieties and is commonly seen planted in private yards as well as public buildings and parks. The common type is quite cold hardy, growing optimally in USDA zone 8, but withstanding zones 7-10 comfortably. The subspecies (or variety) rusticana is supposed to withstand temperatures down to -15 C (5 F) as well as extended cold periods and snow cover. To ensure the flower buds do not blast in cold winter areas, it is best to afford them some protection from dry winter winds at least.
Camellia japonica is one of Japan’s finer flowering trees. If for no other reason it should be planted for its lovely flowers, but in truth it is a great plant in all respects. It is the perfect subject for a semi-shady courtyard, at a forest edge, or in the shade of tall conifers.