Strophanthus mortehanii De Wild.
Strophanthus mortehanii De Wild. is a species of plant in the family Apocynaceae. It is native to tropical and subtropical regions of Africa, particularly found in Central African Republic, Cameroon, and Congo.
Common Names
This plant species has different common names in different regions. Some of the common names include:
- Bongo (Bakumutu)
- Borubobe (Kaka)
- Lunga (Lingala)
- Mabanga (Ngumba)
- Mulele (Ngwaka)
- Ngnevo (Mbomam)
Uses
The plant has a long history of medicinal use in Africa. Its root, bark, and seeds are used for various medicinal purposes. The locals use it to treat heart problems, snakebites, and as a general tonic. The plant contains several cardiac glycosides and is used as a treatment for heart failure. It is also used to stimulate blood circulation and control irregular heartbeat. The seeds can be used to make arrow poison and as a fish poison.
General Appearance
Strophanthus mortehanii De Wild. is a woody, climbing plant that reaches heights of up to 30 feet. Its leaves are glossy and evergreen, and the plant produces fragrant flowers that vary in color from greenish-white to yellow. The fruit is a woody capsule that contains numerous seeds with a tuft of white hairs at one end.
The plant's stem is straight and cylindrical, with a smooth gray bark. The stem bears opposing leaves that are oval-shaped and pointed at the tip. The leaves are 7 to 10 cm long and have a bright green color. The flowers of Strophanthus mortehanii De Wild. are star-shaped and have five petals. They are about 2-4 cm in diameter and are very fragrant.
Light Requirements
Strophanthus mortehanii De Wild. requires bright but indirect sunlight to grow properly.
Temperature Requirements
Strophanthus mortehanii De Wild. prefers warm temperatures between 18°C to 28°C to grow. Temperatures below 10°C can be detrimental to its growth.
Soil Requirements
The plant requires well-draining soil with a pH range of 5.5 to 6.5. It prefers loamy soils with adequate amounts of organic matter.
Water Requirements
The plant needs regular watering but ensure that the soil does not become waterlogged. Allow the soil to dry partially between watering.
Fertilizer Requirements
Strophanthus mortehanii De Wild. benefits from regular nutrient supply. You can use a balanced fertilizer that contains equal proportions of nitrogen, phosphorus, and potassium. Use the fertilizer once or twice per month during the growing season.
Cultivation methods
Strophanthus mortehanii De Wild. is a climbing plant that requires support for optimal growth. It thrives in well-drained soils with a pH range of 5.5 to 7.0 and prefers full or partial sunlight. The plant can be propagated by seeds or cuttings.
Watering needs
The plant requires moderate watering during the growing season and minimal watering during the dormant season. Water the plant deeply once a week during the growing season. Ensure that the soil is moist and well-drained. Avoid overwatering as it can lead to root rot.
Fertilization
Strophanthus mortehanii De Wild. requires regular fertilization to promote healthy growth. Apply a balanced fertilizer every two weeks during the growing season. Alternatively, you can use organic fertilizers like compost or manure. Ensure that you follow the instructions on the fertilizer package for best results.
Pruning
Pruning helps to keep the plant in shape and promote blooming. Prune the plant in late winter or early spring before new growth begins. Cut back any dead, damaged or diseased stems to the base. Also, remove any overcrowded or crossing branches. Train the remaining stems to climb the support structure for optimal growth.
Propagation of Strophanthus mortehanii De Wild.
Strophanthus mortehanii De Wild. can be propagated both by seed and vegetatively.
Propagation by Seed
Seeds of Strophanthus mortehanii are collected from mature fruits. The seeds have a short viability period and must be sown immediately after their collection. They are best sown in a mixture of sand and soil in equal proportions. Alternatively, they can be sown in trays or seedling pots and covered with a thin layer of soil. Moisture must be maintained during the germination period, which usually takes 2-3 weeks. Germination can be improved by soaking the seeds in hot water for a few hours before sowing.
Vegetative Propagation
Strophanthus mortehanii can be propagated vegetatively by stem cuttings or layering. Stem cuttings should be taken from the parent plant during the rainy season when the plant is actively growing. The cuttings, about 20-30cm long, must be treated with rooting hormone and inserted into a rooting medium. The medium should be kept moist, and the cuttings should root within 4-6 weeks.
Layering is also an effective method of propagating Strophanthus mortehanii. This involves bending a low-hanging branch to the ground and covering it with soil. The branch will eventually produce roots, and when it is well established, it can be separated from the parent plant and transplanted to its new location.
Disease Management
Strophanthus mortehanii De Wild. is generally a hardy plant that is resistant to many diseases. However, some possible diseases that may affect the plant include:
- Fungal leaf spot: This is a common fungal disease that affects many plants, including Strophanthus mortehanii De Wild. It appears as brown or black spots on the leaves, and it can cause defoliation if not controlled early. To manage this disease, remove and destroy the infected leaves and ensure proper spacing between plants for improved airflow.
- Root rot: Root rot can be caused by various soil-borne fungi and can cause wilting, yellowing, and stunted growth in the plant. To manage this disease, ensure proper drainage and avoid overwatering the plant. If the disease is severe, it may be necessary to remove and destroy the affected plant.
- Anthracnose: This is a fungal disease that affects the leaves and stems of the plant, causing them to turn black and wilt. To manage this disease, remove and destroy the infected plant parts, and avoid overhead watering.
Pest Management
Serious pest problems are uncommon in Strophanthus mortehanii De Wild. However, the plant may be affected by the following pests:
- Aphids: Aphids can suck the sap from the leaves and stems of the plant, causing stunted growth and distorted leaves. To manage this pest, spray the plant with a mixture of water and soap or neem oil.
- Mealybugs: Mealybugs are small, soft-bodied insects that suck sap and excrete honeydew, which attracts ants and encourages the growth of sooty mold. To manage this pest, remove and destroy the affected plant parts and use insecticidal soap or neem oil to control the infestation.
- Caterpillars: Caterpillars can cause significant damage to the leaves and stems of the plant, leading to defoliation. To manage this pest, handpick the caterpillars and use biological controls such as Bacillus thuringiensis (BT) or spinosad-based insecticides.
