Introduction
Garcinia usambarensis Engl., commonly known as African gamboge tree, is a species of flowering plant from the Clusiaceae family. This plant is native to the eastern parts of Africa, including Kenya, Tanzania, and Uganda.
Appearance
The African gamboge tree can grow up to 25 meters tall with a trunk diameter of up to 1 meter. The bark is dark brown while the tree has a dense canopy of glossy green leaves. The branches are somewhat droopy, the tree's leaves are usually oblong, evergreen, and have a smooth top surface. The flowers are large, white, and fragrant.
Uses
The tree’s fruit, also known as African mangosteen, has become popular in several countries for its valuable medicinal properties. The fruit contains hydroxycitric acid (HCA), which has been shown to aid weight loss and reduce appetite. Additionally, the tree's bark and leaves have also been used for medicinal purposes.
Importantly, the fruit is edible, and its pulp is sweet and sour. The fruits from the African gamboge trees are utilized for their flavor in the food industry, primarily in jams, jellies, and sauces. Additionally, the plant’s foliage is used for fodder and is also utilized for firewood and charcoal production. Finally, the African Gamboge tree is used as an ornamental tree in gardens and parks.
Conclusion
Overall, the African gamboge tree is a valuable plant for local communities, particularly for its fruits, bark, and leaves. Additionally, this tree is an important source of food, fodder, and fuel in East Africa. Its ornamental nature also makes it a great choice for beautifying gardens and parks.
Typical Growth Conditions for Garcinia usambarensis Engl.
Known for its medicinal properties and its edible fruit, Garcinia usambarensis Engl. is an evergreen tree that is endemic to East Africa, particularly in Tanzania and Kenya. It is commonly found in tropical rainforests and typically grows up to 20 meters tall.
Light Requirements
Garcinia usambarensis Engl. thrives well in full sun to partial shade. It requires at least 6 hours of direct sunlight each day to produce the best yields. If planted in an area with intense sunlight, it is best to provide some shade in the afternoon.
Temperature Requirements
This plant requires a hot and humid climate to grow optimally. A temperature range between 27°C and 32°C (80.6°F-89.6°F) is ideal. It is sensitive to frost and cannot withstand temperatures lower than 15°C (59°F).
Soil Requirements
Garcinia usambarensis Engl. grows best in well-draining soils that are rich in organic matter. The soil pH should range between 6 and 7.5. It is also important to ensure that the soil is consistently moist as the plant cannot tolerate drought conditions.
Additionally, fertilizers rich in nitrogen, potassium, and phosphorus should be added to the soil to ensure that the plant receives adequate nutrients required for proper growth and development.
Cultivation of Garcinia usambarensis Engl.
Garcinia usambarensis Engl. prefers to grow in areas with a moderately humid climate and temperatures ranging from 15 to 30°C. It does not tolerate extreme temperatures and frost. The plant requires well-draining, moderately fertile soils. Before planting, the soil should be loosened and enriched with organic matter, such as compost or decomposed leaves.
Watering Needs
Garcinia usambarensis Engl. requires regular watering, especially during the dry season. However, the plant does not cope well with excessive moisture, and waterlogging should be avoided. Adequate drainage is essential to prevent waterlogging and root rotting.
Fertilization
Garcinia usambarensis Engl. will benefit from regular fertilization with a balanced, slow-release fertilizer. Fertilization should be done during the growing season, and the amount of fertilizer applied should be based on the plant's size and age. Adequate levels of nutrients, especially nitrogen, phosphorus, and potassium, will promote healthy growth and fruit production.
Pruning
Garcinia usambarensis Engl. requires minimal pruning, and it is generally only done to promote an open structure and remove dead or damaged branches. Pruning should be done in late winter or early spring before the onset of new growth. It is advisable to sterilize pruning tools with a solution of one part bleach to nine parts water to avoid the spread of diseases.
Propagation of Garcinia usambarensis Engl.
Garcinia usambarensis Engl., commonly known as the African gamboge, is a flowering plant species native to East Africa. Propagation of this plant can be done using several methods, including seeds, cuttings, and air layering.
Seeds Propagation
Propagation of Garcinia usambarensis through seeds is feasible, but it may not be a reliable method because getting seeds from a mature plant may be difficult. Nevertheless, if the seeds are available, they can be sown in a well-draining potting mix, at a depth of approximately 1 inch.
It is essential to maintain a constant moisture level of soil during the germination period, which can take anywhere from one to two months. The germination temperature should be around 77 F or 25 C. Once the seedlings develop their second set of leaves, they can be transplanted into larger pots or directly into the garden.
Cuttings Propagation
Garcinia usambarensis can also be propagated through cuttings taken from semi-hardwood. Collect cuttings that are around 6 inches long from a mature plant in late summer or early fall. Remove all the leaves from the lower two-thirds part of the cutting. Dip the lower end of the cutting into rooting hormone powder and plant it into a potting mix or coconut coir.
Water the cutting thoroughly and cover with a plastic bag or jar to maintain a warm and humid environment. The cutting should root in about 4 to 6 weeks, and after the roots develop, it can be transplanted into a larger pot or directly into the garden.
Air Layering Propagation
Air layering propagation is another suitable method for propagating Garcinia usambarensis. This technique involves wounding the stem to stimulate root production and then using a rooting hormone, sphagnum moss, and plastic wrap to promote root growth in the area of the injury.
Collect a branch that is not woody and doesn't have any flowers or fruits. Make a small incision in the bark about six inches from the tip of the branch. Then wrap sphagnum moss around the stem and cover it with plastic wrap. After about a month, roots should appear. Once the roots have grown to a sufficient size and number, cut the branch beneath the newly formed root ball and transplant it into a potting mix or directly into the garden.
Overall, stakeholders can use any of the propagation techniques mentioned above to propagate Garcinia usambarensis successfully. The choice of a particular method could depend on the grower's preference.
Disease and Pest Management for Garcinia usambarensis Engl.
Garcinia usambarensis Engl. is an ornamental tree native to East Africa. Like other plant species, it is vulnerable to pests and diseases that can affect its health, growth, and productivity. The following are some of the most common diseases and pests that can affect Garcinia usambarensis Engl. and ways to manage them:
Common Diseases
Leaf Spot Disease: Leaf spot disease is caused by fungal pathogens that infect the leaves of the tree, leading to brown spots that eventually turn yellow and cause leaf drop. The disease can be managed by removing infected leaves, pruning affected branches, and applying fungicides.
Root Rot: Root rot is a fungal disease that affects the roots of the plant, leading to reduced growth, yellowing of leaves, and eventual death of the tree. The disease can be managed by improving soil drainage, avoiding overwatering, and applying fungicides.
Common Pests
Scale Insects: Scale insects are small, oval-shaped insects that form a protective covering on the leaves and stems of the plant. They suck sap from the leaves and stems, leading to reduced growth and productivity. The pests can be managed by pruning affected parts, applying insecticidal soap, or using horticultural oil.
Caterpillars: Caterpillars are the larvae of moths and butterflies that feed on the leaves of the tree, leading to leaf drop and reduced growth. They can be managed by manually removing them from the tree or using biological control agents such as Bacillus thuringiensis.
Mites: Mites are small, spider-like pests that feed on the leaves of the tree, causing yellowing and browning of leaves, and eventual defoliation. They can be managed by applying insecticidal soap or horticultural oil, or by introducing natural predators such as predatory mites.
By following these disease and pest management practices, the health and productivity of Garcinia usambarensis Engl. can be ensured, keeping the ornamental tree in good condition for years to come.
