Overview
Pentadesma gabonensis Pierre ex A.Chev. is a tall forest tree in the family Clusiaceae, native to tropical Africa in countries such as Gabon, Cameroon, and Congo. It is a valuable source of various products that support the livelihood of local communities.
Common Names
Pentadesma gabonensis has various common names, including African butter tree, African elemi, and wild rubber tree. In Cameroon, it is known as munguella, in Gabon as samba, and in Congo as mbimbi.
Uses
The tree has many uses, both traditional and modern. The fruit pulp is edible and consumed locally, while the seeds yield a valuable oil, known as moabi butter. Moabi butter is used in cosmetic and pharmaceutical industries due to its moisturizing and soothing properties. The wood is strong and hard, making it ideal for crafting of furniture, canoes, and other tools. The bark is used in traditional medicine for various ailments.
General Appearance
Pentadesma gabonensis is a tall tree that grows up to 40 meters in height, with a straight trunk and a dense crown of leaves. The leaves are simple, alternate, and dark green. The flowers are white to yellowish and occur in small clusters. The fruit is a large woody capsule with five compartments, each containing one seed covered with a fleshy aril. The seeds are about 2-3 cm in diameter and have a hard outer shell.
Light requirements
Pentadesma gabonensis requires a good amount of light to grow properly. It can grow in both full sun and partial shade conditions. It is important to provide adequate shading if the plant is grown in an area that is too hot.
Temperature requirements
The plant grows well in a temperature range of 25 to 30 °C. It prefers warm and humid conditions, so it grows best in tropical and subtropical climates. The plant may not tolerate frost, so it should be protected in regions where the temperature drops below 10 °C.
Soil requirements
The ideal soil for Pentadesma gabonensis is sandy or loamy soil. It needs soil with good drainage to avoid waterlogging. The pH of the soil should be between 5.5 and 7.5. The plant can tolerate both acidic and alkaline soils but does not grow well in extremely acidic or alkaline soils. A well-drained and fertile soil can help the plant grow properly.
Cultivation
Pentadesma gabonensis Pierre ex A.Chev., commonly known as African nutmeg, is a tropical species that thrives in regions with warm temperatures and high humidity. It is essential to simulate such conditions when cultivating this plant in cooler regions. This can be achieved by growing the plant in a greenhouse or indoors near a south-facing window.
African nutmeg prefers well-draining soil that is rich in organic matter. Planting the seedlings in soil with a pH between 5.5 - 6.5 is recommended.
Young plants do not tolerate direct sunlight well, so they need to be exposed to indirect light gradually. Daily exposure to direct sunlight should not exceed 3 - 4 hours.
Watering Needs
African nutmeg requires frequent watering, especially during the growing season. This plant prefers moist soil, but it must be well-drained to prevent waterlogging.
A general rule of thumb is to water Pentadesma gabonensis when the top inch of soil is dry. Overwatering or underwatering can cause damage to the plant.
Fertilization
Fertilizer is essential for the healthy growth of Pentadesma gabonensis. It is recommended to use organic fertilizers and apply them during the growing season (spring and summer).
The fertilizer application rate will depend on the age of the plant and the nutrient requirement of the soil. It is best to start with a lower amount of fertilizer and gradually increase the application rate to avoid burning the roots.
Pruning
Pruning is essential to maintain the shape and health of the Pentadesma gabonensis plant.
Start pruning young plants to encourage branching and shape development. Mature plants can be pruned to remove dead or diseased branches, remove crossing branches, and to control the height of the plant.
Pruning African nutmeg can be done at any time of year, but avoid pruning during the dormant period to prevent stress on the plant.
Propagation of Pentadesma gabonensis Pierre ex A.Chev.
Pentadesma gabonensis Pierre ex A.Chev. is commonly propagated through seeds, air layering, and stem cuttings.
Propagation through seeds
Seeds are collected from ripe fruits and sun-dried to remove the fleshy pulp. After drying, the seeds are scarified with sandpaper or a file to aid in germination. The scarified seeds are soaked in water for at least 24 hours before planting to soften the seed coat.
The planting medium for the seeds should be well-draining and rich in organic matter. The seeds are planted at a depth of 2-3 cm and watered regularly.
Air layering
Air layering is a preferred method for propagation in Pentadesma gabonensis since it ensures that the resulting plant is genetically identical to the parent plant. To air layer, a section of the stem is selected, and a 2cm deep ring of bark is removed using a sharp knife. The exposed area is wrapped with moist sphagnum moss and covered with foil to retain moisture. After a few months, roots will form in the moss, and the stem can be cut off and planted as a new plant.
Propagation through stem cuttings
Pentadesma gabonensis can also be propagated through stem cuttings taken from healthy and mature plants. Cuttings are taken in the spring or summer months and should be about 15-20 cm long. The lower leaves are removed, and the cuttings are planted in a well-draining potting mix with a rooting hormone. The cuttings should be kept in a warm and humid area until roots develop.
Disease Management
The plant Pentadesma gabonensis is prone to several diseases, including anthracnose, leaf spots, and root rot. Anthracnose, caused by the fungus Colletotrichum gloeosporioides, appears as small, sunken lesions on leaves, stems, and fruits. Leaf spots are caused by various fungi and appear as brown or black spots on leaves. Root rot, caused by various soil-borne fungi, leads to the decay of the roots and can cause wilting and eventual death of the plant.
To manage anthracnose, affected leaves and fruits should be removed and destroyed. Fungicides containing copper or thiophanate-methyl can also be used to prevent further infection. To manage leaf spots, affected leaves should be removed and destroyed. Fungicides containing chlorothalonil or mancozeb can also be used to prevent further infection. To manage root rot, affected plants should be removed and destroyed. Soil drenches with fungicides containing thiophanate-methyl, azoxystrobin, or mefenoxam can also be used to prevent further infection.
Pest Management
Pentadesma gabonensis is also susceptible to pests, including mealybugs, scale insects, and aphids. Mealybugs appear as white, cottony masses on the stems and leaves and can cause stunted growth and yellowing of the leaves. Scale insects appear as small, raised bumps on the stems and leaves and can cause yellowing and curling of the leaves. Aphids suck the sap from the leaves and stems and can cause wilting and deformation of the plant.
To manage mealybugs, affected plants should be isolated and treated with insecticidal soap or neem oil. Ants, which can transport mealybugs, should also be controlled. To manage scale insects, affected plants should be treated with horticultural oil or insecticidal soap. To manage aphids, affected plants should be sprayed with a strong jet of water or treated with insecticidal soap or neem oil.
