Strophanthus kombe Oliv.
Strophanthus kombe Oliv. is a vine plant that belongs to the family Apocynaceae. It is native to tropical Africa, specifically in countries such as Cameroon, Gabon, Congo, and Tanzania. The plant is also commonly known as kombe arrow poison, ouabain, and African arrow poison.
Appearance
The plant is a woody vine that can grow up to 10 meters long. It has glossy, dark green leaves that are elliptic in shape and can grow up to 15 cm in length. Its flowers are trumpet-shaped and have a creamy-white color with purple-red markings. The fruit of the plant is a follicle, which contains seeds that are winged and flat, allowing for easy dispersal by the wind.
Uses
The plant is well-known for its medicinal properties. It has been used to treat various illnesses, including heart disease, fever, snake bites, and dysentery. The active compounds found in the plant, called cardiac glycosides, are used to treat heart failure and irregular heartbeats. It is also used in some traditional African cultures to make arrow poison for hunting.
Aside from its medicinal uses, Strophanthus kombe Oliv. is also used for ornamental purposes. Its attractive flowers are often used in gardens and landscaping due to their unique, trumpet shape and beautiful color.
However, it is important to note that the plant is toxic and should be used with caution. Its sap and seeds contain deadly toxins that can cause cardiac arrest and death if ingested in large quantities.
Light Requirements
Strophanthus kombe Oliv. prefers partially shaded to full sunlight conditions for optimal growth. However, it can tolerate full shade, especially during the hottest periods of the year.
Temperature Requirements
Strophanthus kombe Oliv. grows best in warm climates with average temperatures between 20°C and 30°C. It can tolerate temperatures as low as 10°C but not frost. Therefore, it is not suitable for cultivation in areas where the mean annual temperature is below 10°C.
Soil Requirements
Strophanthus kombe Oliv. prefers well-draining soils with a pH range of 5-7. It grows best in sandy, loamy, or gravelly soils, though it does not do well in clay soils. It requires a high level of organic matter and nutrients for optimal growth. Therefore, regular fertilization is necessary for optimal production.
Cultivation Methods
Strophanthus kombe Oliv.is a perennial vine that is typically grown in warm and tropical climates. The plant grows best in well-draining soil that is rich in organic matter. It requires a lot of sunlight to grow, making it an excellent choice for gardeners.
When planting, it's recommended to prepare the soil by adding compost and sand to improve the drainage. The plant should be located in full sun to promote growth. The plant is propagated through seeds, and it's essential to ensure that the soil remains moist until germination to encourage healthy growth.
Watering Needs
The plant requires frequent and consistent watering throughout the growing season. The soil should be kept moist, but not waterlogged, as this can damage the roots. Watering should be reduced in the colder season to prevent waterlogging.
It's essential to ensure that the plant has proper drainage to avoid water stagnation, which can cause root rot. Where possible, a drip irrigation system should be used to supply water to the plant to avoid wetting the foliage and flowers, which can lead to fungal diseases.
Fertilization
Strophanthus kombe Oliv. requires regular fertilization during the growing season to promote healthy growth and flowering. A balanced fertilizer rich in nitrogen, phosphorus, and potassium is best for the plant. Organic fertilizers, such as compost and manure, can also be added to the soil to improve fertility.
The fertilizers should be applied to the soil around the base of the plant and not onto the foliage or flowers, which may cause burns. Miracle-Gro provides excellent fertilizers for this plant and many others.
Pruning
Pruning is necessary to shape the plant and maintain its size, removing any dead or dying stems and leaves. It should be carried out in the early spring, just before new growth appears. Cutting back the plant encourages the growth of healthy new stems and foliage.
Deadheading the spent flowers by snipping them off also encourages the production of new flowers. When pruning, it's essential to use clean, sharp tools to avoid damaging the plant. Avoid pruning during the cold season when the plant is dormant.
Propagation of Strophanthus kombe Oliv.
Strophanthus kombe Oliv. can be propagated through different methods, including seed propagation and vegetative propagation.
Seed propagation
Seeds of Strophanthus kombe Oliv. are small and require pre-treatment before sowing. The seeds need to be soaked in water for a minimum of 24 hours or scarified to improve germination rates. Scarification is a process that involves breaking the hard seed coat to allow moisture to penetrate. This can be done manually, by rubbing the seeds with sandpaper, or using chemicals such as concentrated sulfuric acid.
After pre-treatment, the seeds can be sown in a well-draining seed tray or potting mix. The seeds require a warm and humid environment for germination. Therefore, it is recommended to cover the seed tray with a plastic wrap or place the pot in a propagator. Germination usually occurs within two to four weeks.
Vegetative propagation
Strophanthus kombe Oliv. can also be propagated through vegetative means, such as stem cuttings or layering.
Stem cuttings are taken from healthy plants during the growing season, and the cuttings should be around four inches long. The base of the cutting should be dipped in a rooting hormone before planting in a well-draining potting mix. The plants should be kept in a humid and warm environment until roots have formed, which usually takes between four to six weeks.
Layering is a process of rooting a branch while still attached to the parent plant. A small part of the stem is buried in the soil while still attached to the plant. Once roots have formed, the new plant can be separated from the mother plant and potted for growing.
Disease and Pest Management for Strophanthus kombe Oliv.
Strophanthus kombe Oliv. is a perennial woody climber that is native to Africa and commonly grown for its medicinal value. Disease and pest management are crucial for the health and productivity of this plant. The following are some common diseases and pests that might affect Strophanthus kombe Oliv. and ways to manage them:
Diseases
Fungal blight: Fungal blight is a common disease that affects Strophanthus kombe Oliv. The symptoms of this disease include brown and black spots on the leaves, stem, and flowers of the plant. To manage this disease, it is essential to remove the infected parts of the plant and treat the plant with a fungicide.
Root rot: Root rot is another common disease that is caused by fungus and affects the roots of the plant. Overwatering and poor drainage are the major causes of this disease. To manage this disease, it is essential to reduce watering and improve the drainage system. Additionally, treating the plant with a fungicide can be helpful in managing this disease.
Pests
Aphids: Aphids are small, soft-bodied insects that attack the leaves and stem of Strophanthus kombe Oliv. The symptoms of this pest attack include yellowing of leaves, stunted growth, and sooty mold. To manage this pest, it is essential to wipe off the aphids with a damp cloth or use insecticidal soap.
Spider mites: Spider mites are tiny pests that are difficult to spot. The symptoms of this pest attack include webbing on leaves, yellow and brown spots on leaves, and defoliation. To manage this pest, it is essential to improve the humidity around the plant by misting the leaves with water. Additionally, spraying insecticidal soap can be helpful in managing this pest.
Mealybugs: Mealybugs are small insects that are covered with a white, powdery substance. The symptoms of this pest attack include wilting of leaves, yellowing of leaves, and stunted growth. To manage this pest, it is essential to remove the infected parts of the plant and treat the plant with insecticidal soap or neem oil.
Managing pests and diseases of Strophanthus kombe Oliv. involves a combination of preventive, cultural, and chemical control measures. Proper sanitation practices such as removing infected parts of the plant are essential to prevent the spread of diseases. Additionally, monitoring the plant regularly for signs of pests and diseases and taking timely action can help to manage them effectively.
