Camphor or Cinnamomum camphora is a low-maintenance evergreen tree that can be a great choice for your garden. As the tree does not require much care, you can easily plant it without hassle. Camphor tree is usually used for its valuable bark, which serves as a very popular spice used in the kitchen. Belonging to the family Lauraceae, this tree originated in places like India, China, Japan, etc. Camphor has a lot of health benefits, which is why many people are now showing interest in growing the tree in their gardens and yards.
I. Appearance and Characteristics
Camphora officinarum is a species of evergreen tree that is commonly known under the names camphor tree, camphorwood or camphor laurel.
Camphora officinarum is native to China south of the Yangtze River, Taiwan, southern Japan, Korea, India, and Vietnam, and has been introduced to many other countries. It grows up to 20–30 m (66–98 ft) tall. In Japan, where the tree is called kusunoki, five camphor trees are known with a trunk circumference above 20 m (66 ft), with the largest individual, Kamō no Ōkusu (蒲生の大楠, “Great camphor of Kamō”), reaching 24.22 m.
The leaves have a glossy, waxy appearance and smell of camphor when crushed. In spring, it produces bright green foliage with masses of small white flowers. It produces clusters of black, berry-like fruit around 1 cm (0.39 in) in diameter. Its pale bark is very rough and fissured vertically.
Certain trees in Japan are considered sacred. An example of the importance of a sacred tree is the 700-year old camphor growing in the middle of Kayashima Station. Locals protested against moving the tree when the railway station had to be expanded, so the station was built around it.
II. How to Grow and Care
Sunlight
The Cinnamomum camphora has a round canopy, so it enjoys full sun to perform its best. So, provide the entire canopy with at least six hours of direct sun for those gorgeous green leaves. Still, your camphor trees can tolerate some partial shade, but for full potential growth, direct sunlight is best.
So keep a safe distance between this tree and your home.
Temperature and Humidity
The maintenance when you have the camphor tree in the landscape is minimal. But it helps to grow trees in warm climates with high humidity. The best agriculture plant in USDA hardiness zones 9b to 11.
If you live in a climate where it gets freezing, we recommend covering your trees with some agricultural fleece. For potted camphor trees, you can keep the plant outdoors in summer but bring them inside when the temperature drops.
Watering
This tree requires a moist, tropical environment with lots of water. In its natural environment, camphor tree receives around 150 days of rain each year. Depending on your climate, you will need to regularly water your plant so that the soil is always slightly moist. Always check that the top 5 cm of soil is dry before watering again. Because of the chemicals in tap water, filtered water or collected rainwater is best. If growing indoors, lightly mist the leaves every week.
Soil
The fantastic thing is that camphor trees adapt to different soils. But they prefer growing in fertile sandy soil and have a broad pH level. The range of the soil needs to be from acidic 4.3 to alkaline 8.0.
Fertilizing
Your camphor tree should be fertilized every 2-4 weeks from spring to fall, with an 8-3-9 fertilizer. A quarter cup of fertilizer per 4.5 m squared of root zone space is ideal. Be sure to spread this to the outer edges of the root zone too, so that all of the roots will benefit. Indoor plants will need to be fertilized in the winter too.
Pruning
While the maintenance is minimal with watering, camphor trees need regular trimming when young and occasional care with pruning when mature. It helps to prune branches growing low when young to provide compact growth.
Cut branches back, making sharp, clean cuts flush next to the stem where it originates from using sterilized pruning shears. For example, you can prune branches growing near the base to develop a single strong main trunk and remove branches on the trunk, leaving them standing every 30 inches apart.
Also, remove damaged or diseased branches at any time of the year and prune them back in winter to control growth. We do not recommend blunt cutting or topping camphor trees as it creates more dead branches that can fall.
Even using a chainsaw constantly results in problems, and at times you may need professional trimming done by an arborist.
Propagation
Another exciting thing is that you can use your camphor tree as a spice. You can remove the inner bark into thin strips to drive in the sun. Once dry, it starts to curl like twigs, and you can ground them into powder.
But ensure that the tree is at least three years old.
When camphor trees in the home landscape grow, it produces thousands of berries you can harvest for seed propagation during summer. Leave the fruit to dry in a shady spot for about three days before you rinse the seeds. Then leave them to dry further and plant them within ten days.
The seedlings germinate in 20 days, will need loads of attention, and are the best way to propagate your tree.
Pests and Diseases
The camphor tree can have its fair share of problems, like leaves turning brown. It can result from high salt levels in the soil caused by fertilizers. We recommend changing the soil in the ground with fresh ones and using a different feed.
Another concern is leaves dropping, which can result from overwatering, and if the soil is saturated, mix in some more sand. Doing this will help prevent root rot as well. Finally, small brown spots on the foliage can be leaf spots caused by a fungus.
The best is to remove branches infected with the disease to prevent the spread of the fungus. Your camphor tree can also suffer from stripe canker that starts in the soil. Insects that bother your tree are mealybugs, and you can remove them by washing the leaves with lukewarm water.
Or prune the infested leaves to reduce the risk of spreading. Other common concerns your trees are susceptible to are foliar disease, brown root, blight leaf spot, seedlings blight, and verticillium wilt.
III. Cinnamomum Camphora Varieties
There are different types of Cinnamomum camphora trees known that you can look at here:
- Yongjin
The tree sprouts in early spring under full sun and has yellow buds with newer leaves in a golden color. The main vein area is reddish and turns light yellow when fully mature. The flower stalks are golden yellow with light yellow fruit turning purple-black.
- Xiaguang
As with the other camphor trees, you find it growing well in full sun. The buds are red with new red leaves turning pale green to yellow-white in summer. After it flowers, the berries develop on yellow stalks turning purple and black.
- Yuhuang
The tree thrives in full sun with bright yellow buds with yellow leaves and matures to pale green.
IV. Uses and Benefits
- Ornamental uses
Camphor tree is often planted by landscapers near streets and walkways, giving them enough room to grow tall with a wide umbrella shape. These trees are also prized for their minty aroma. Shade-loving ferns are often used to create attractive groundcover beneath these trees.
- Other uses
C. camphora is cultivated for camphor and timber production. The production and shipment of camphor, in a solid, waxy form, was a major industry in Taiwan prior to and during the Japanese colonial era (1895–1945). It was used medicinally and was also an important ingredient in the production of smokeless gunpowder and celluloid. Primitive stills were set up in the mountainous areas in which the tree is usually found. The wood was chipped; these chips were steamed in a retort, allowing the camphor to crystallize on the inside of a crystallization box after the vapour had passed through a cooling chamber. It was then scraped off and packed out to government-run factories for processing and sale. Camphor was one of the most lucrative of several important government monopolies under the Japanese.
The wood has an insect-repellent quality.
- Camphor
Camphor is a white crystalline substance, obtained from the tree C. camphora. Camphor has been used for many centuries as a culinary spice, a component of incense, and as a medicine. It is also an insect repellent and a flea-killing substance.
- Chemical constituents
The species contains volatile chemical compounds in all plant parts, and the wood and leaves are steam distilled for the essential oils. Camphor laurel has six different chemical variants called chemotypes, which are camphor, linalool, 1,8-cineole, nerolidol, safrole, and borneol. In China, field workers avoid mixing chemotypes when harvesting by their odour. The cineole fraction of camphor laurel is used in China to manufacture fake “eucalyptus oil”.
The chemical variants (or chemotypes) seem dependent upon the country of origin of the tree. e.g., C. camphora grown in Taiwan and Japan is normally very high in linalool, often between 80 and 85%. In India and Sri Lanka, the high camphor variety/chemotype remains dominant. C. camphora grown in Madagascar, though, is high in 1,8-cineole (averaging between 40 and 50%). The essential oil from the Madagascar trees is commercially known as ravintsara.
V. Harvesting and Storage
To use camphor tree as a spice, the inner bark of the tree should be removed in thin strips and dried in the sun. Once thoroughly dried, it can be curled into sticks or ground into a powder. The plant must be at least three years old before any bark is removed.
