Origin
Griffonia tessmannii (De Wild.) Compère is an evergreen plant that belongs to the Fabaceae family. It is native to West Africa, specifically in the countries of Cameroon, Gabon, and the Congo.
Common Names
Griffonia tessmannii is more commonly known as African black bean, Congo bean, and Kanya.
Uses
The seeds of Griffonia tessmannii are majorly used, and they are known to have medicinal properties. The seeds contain high levels of 5-HTP, which is converted to serotonin in the brain, making it useful in the treatment of depression, anxiety, and sleep disorders. Additionally, the seeds have been used to treat obesity, relieve migraines, and alleviate premenstrual syndrome (PMS).
Griffonia tessmannii is used in African cultures to produce dye. The bark of the tree is stripped and boiled to produce a deep brown dye used in clothing and textiles. The seeds are also used for food, especially as a soup thickener.
General Appearance
Griffonia tessmannii is a large perennial shrub or tree that can grow to a height of ten meters. The plant has a bushy appearance and features scaly bark that is grey to brown in color. The leaves are alternate, dark green, and glossy, measuring between 8-15 cm long. The flowers are small, light green, and contain five petals. The fruit of the plant is a pod, which is between 5-20 cm long and 1.5-3 cm wide. Each pod contains up to ten seeds shaped like a lens, which are dark brown to black in color.
Growth Conditions of Griffonia tessmannii (De Wild.) Compère
Light: Griffonia tessmannii grows well in a partially shaded location, receiving about four to six hours of direct sunlight daily. It cannot tolerate direct sunlight for extended periods.
Temperature: This plant requires warm temperatures with a minimum of 18°C (65°F) and a maximum of 30°C (86°F). It can survive in cooler temperatures, but growth is slower.
Soil: Griffonia tessmannii prefers a well-draining, slightly acidic soil with a pH range of 6 to 7.5. The soil should also be rich in organic matter. A mix of peat, perlite, and vermiculite is suitable for this plant.
Water: The plant prefers consistent moisture, but it is important to avoid overwatering, which can lead to root rot. Water the plant every two to three days, depending on the weather. The soil should be moist but not waterlogged.
Fertilizer: Griffonia tessmannii requires a balanced fertilizer, with equal parts of nitrogen, phosphorus, and potassium, applied once a month during the growing season. Be careful not to over-fertilize, as this can damage the plant.
Propagation: This plant can be propagated through stem cuttings or seeds. Stem cuttings should be taken in the spring or summer and placed in a rooting hormone before being transferred to a potting mix. Seeds can be harvested in the fall and sown in the spring in a seed tray.
Cultivation of Griffonia tessmannii
Griffonia tessmannii can be propagated through seeds or cuttings. However, seeds are the most common method used. The seeds should be soaked in water for 24 hours before they are sown in a potting mix. The potting mix should consist of peat moss, perlite and vermiculite in equal proportions.
The potting mix should be kept moist at all times but not waterlogged. The seeds should begin to germinate within two weeks, and the seedlings should be transplanted to individual containers when they have reached a height of four inches.
Watering Needs of Griffonia tessmannii
Griffonia tessmannii prefers medium to high humidity and moist soil. The soil should be kept moist but not waterlogged. Overwatering can lead to root rot, so it is important to ensure that the soil is well-draining. Watering should be reduced during the winter months when the plant goes dormant.
Fertilization of Griffonia tessmannii
Griffonia tessmannii should be fertilized during the growing season from spring through fall. A balanced fertilizer with a 10-10-10 ratio of nitrogen, phosphorous, and potassium should be used. Alternatively, a slow-release fertilizer can be used according to the manufacturer's instructions.
To avoid overfertilization, it is recommended to dilute the fertilizer to half its strength before application. Fertilizer should not be applied to a dry plant and should be watered in immediately after application.
Pruning of Griffonia tessmannii
Griffonia tessmannii does not require extensive pruning, but removing spent flowers and any dead or damaged leaves is recommended. Pruning should be done in the spring before new growth appears. The plant may become leggy over time, and pinching the tips of the stems can encourage bushier growth.
It is important to use clean, sharp pruning tools to avoid damaging the plant. Any cuts made should be made at a slight angle to avoid water accumulation on the cut surface, which can lead to disease.
Propagation of Griffonia tessmannii (De Wild.) Compère
Griffonia tessmannii (De Wild.) Compère is a woody and climbing plant species that belongs to the family of Fabaceae. The plant is commonly found in tropical regions of Africa, where it grows on rocky outcrops and shady forests. Propagating Griffonia tessmannii can be done through several methods, which include:
Seed propagation
Griffonia tessmannii can be propagated through seeds that are obtained from mature fruits. The seeds should be harvested carefully and cleaned to remove any pulp or debris. The cleaned seeds can then be sown in suitable containers filled with a well-draining potting mix. The containers should be placed in a warm and humid environment with dappled sunlight. Germination of the seeds usually takes between 2 to 4 weeks, after which the seedlings can be transplanted into larger pots or suitable planting sites.
Cuttings propagation
Griffonia tessmannii can also be propagated through stem cuttings. The stem cuttings should be taken from healthy and mature plants and should have at least one node and a few leaves. The cuttings should be treated with rooting hormone and planted in a well-draining potting mix. The planting container should be covered with a plastic bag to maintain high humidity levels. The cuttings usually root in 2 to 4 weeks, after which they can be transplanted into larger pots or suitable planting sites.
Layering propagation
Griffonia tessmannii can also be propagated through layering. The process involves bending a healthy branch or stem to the ground and burying a section of it with soil. The buried section of the stem should be treated with rooting hormone and kept moist at all times. After a few weeks, new roots and shoots should emerge from the buried section of the stem. The new plant can then be separated from the parent plant and transplanted to a suitable site.
Disease Management
Griffonia tessmannii can be susceptible to various diseases, including:
- Anthracnose: This fungal disease can cause leaf spots, twig dieback, and defoliation. To manage anthracnose, remove infected plant parts and apply a fungicide according to label instructions.
- Root rot: Overwatering or poorly-draining soil can lead to root rot, causing wilting, yellowing, and stunted growth. To prevent this disease, plant Griffonia tessmannii in well-draining soil and avoid overwatering.
- Leaf spots: Various fungal pathogens can cause circular or irregular leaf spots on Griffonia tessmannii. Remove infected plant parts and apply a fungicide according to label instructions to manage leaf spots.
Pest Management
Several pests can also affect Griffonia tessmannii, such as:
- Aphids: These small insects can cluster on the undersides of leaves and suck sap from the plant, causing yellowing and stunted growth. To manage aphids, spray the plant with a strong stream of water or apply an insecticidal soap or oil according to label instructions.
- Spider mites: These tiny pests can cause yellowing and stippling on leaves and produce fine webs on the plant. To manage spider mites, remove heavily-infested plant parts and apply an insecticidal soap or oil according to label instructions.
- Caterpillars: Certain types of caterpillars can chew on Griffonia tessmannii leaves, causing unsightly holes and defoliation. To manage caterpillars, handpick and remove them from the plant, or apply a biological control such as Bacillus thuringiensis (Bt) according to label instructions.
