Overview of Strophanthus hispidus A. DC.
Strophanthus hispidus A. DC. is a climbing plant species from the Apocynaceae family that is native to tropical Africa. The plant is also commonly known as the "poison arrow vine" or "kombé." The plant's genus name, "Strophanthus," means "twisted flower," indicating its unique floral structures.
Appearance
Strophanthus hispidus A. DC. is a woody vine that can grow up to 10 meters in height, thanks to its climbing nature. The plant has long shoots with tendrils, which help it cling on to any support around it. The leaves of S. hispidus are usually 5-13 cm long, and they have distinct midribs. The flowers, which bloom from the early summer to late autumn, are tubular and can range from white to cream in color. S. hispidus produces fruits that are oval in shape, and each fruit has two seeds. The plant's seeds are enveloped in soft bristle-like hairs, which are responsible for the "hispidus" in its name.
Uses
Strophanthus hispidus A. DC. has been traditionally used in different African communities for both medicinal and cultural purposes. The plant's bark and seeds contain cardiac glycosides, which have potent medicinal properties. The poison arrow vine has been used to manage different medical conditions, including heart failure, edema, snake bites, and as an emetic. The plant's seeds are also used to produce arrow poison, which has been used by hunters in Africa for centuries. Besides its medicinal uses, S. hispidus also has ornamental value, and it's often grown as an ornamental plant given its attractive flowers.
Light Requirements
Strophanthus hispidus A. DC. grows best in a bright and sunny location. It necesitaes full sun to part shade.
Temperature Requirements
The plant prefers warm temperatures, ranging from 18 to 30 degrees Celsius. It requires a moderate amount of humidity and cannot tolerate frost.
Soil Requirements
The plant grows well in well-draining soils that have a neutral to acidic pH. It prefers loamy soils that are rich in organic matter, but it can also grow in sandy soils. Adequate drainage is necessary to prevent the roots from getting waterlogged.
Cultivation of Strophanthus hispidus A. DC.
Strophanthus hispidus A. DC. is best grown in warm and moist environments with plenty of sunlight. It is essential to choose a site with well-drained soil that is rich in nutrients and has a pH range of 6.0 to 7.5. The ideal temperature for growing this plant is between 18°C and 30°C.
The seeds of the plant can be sown directly into the soil or in trays if you plan to transplant them later. The best time for sowing seeds is in the spring when the soil is warm. Germination should occur within one to four weeks, depending on the condition of the soil.
Watering Needs of Strophanthus hispidus A. DC.
The plant should be watered adequately but not excessively. It is essential to maintain a consistent level of soil moisture to prevent the plant from experiencing drought stress. Water the plant once a week or more often during dry periods, and ensure that the soil is well-drained to prevent waterlogging.
Fertilization of Strophanthus hispidus A. DC.
It is recommended to fertilize the plant with a slow-release organic fertilizer during the growing season. This will ensure that the plant has sufficient nutrients to support healthy growth. Fertilize the plant at the base of the stem, and ensure that the fertilizer is evenly distributed to prevent root burn.
Pruning of Strophanthus hispidus A. DC.
To maintain the shape and size of the plant, it is recommended to prune the plant during the dormant season. Remove any dead or damaged branches, and thin out any overcrowded branches to improve airflow and sunlight penetration. Prune the plant to a height of 1 to 2 meters to encourage bushy growth.
Propagation of Strophanthus hispidus A. DC.
Strophanthus hispidus A. DC. can be propagated through both seed and vegetative methods.
Seed Propagation
Seeds should be collected as soon as the pods begin to dry and split open. The seeds are then washed, cleaned, and soaked in water for 24 hours. After soaking, the seeds can be sown in a well-draining potting mix. Cover the seeds lightly with the potting mix and water well.
It's important to maintain a warm and humid environment around the seedlings after sowing. This can be achieved by covering the pot with plastic or placing it in a propagator. Germination can take up to 6 weeks. Once the seedlings have developed a few leaves, they can be transplanted into their own pots.
Vegetative Propagation
Strophanthus hispidus A. DC. can also be propagated vegetatively through stem cuttings. The best time to take stem cuttings is during the plant's active growing season, which is usually in the spring or summer. Choose a healthy stem and cut a section that is 4-6 inches long. Remove leaves from the lower half of the cutting and dip it in a rooting hormone. Place the cutting in a well-draining potting mix and water well.
The cutting should be kept in a warm and humid environment until roots have developed. This can take several weeks. Once roots have developed, the cutting can be transplanted into its own pot.
Disease Management
Strophanthus hispidus A. DC. is vulnerable to various diseases that can hinder its growth and development.
Anthracnose is a fungal disease that causes wilting, leaf drop, and stem dieback. To prevent anthracnose, prune infected leaves and stems, practice good sanitation by removing debris around the plant, and apply a copper-based fungicide.
Root Rot is also a fungal disease that results in rotting of the roots, leading to reduced water and nutrient uptake. To prevent root rot, avoid overwatering, improve drainage in the soil, and remove infected plants from the area.
Mosaic Virus causes light and dark green mottling of the leaves, stunted growth, and distorted flowers. There is no known cure, so it is recommended to remove the infected plants and prevent cross-contamination.
Pest Management
Strophanthus hispidus A. DC. is also susceptible to pest infestations that can damage the plant.
Aphids are small insects that suck sap from the leaves, causing them to wilt and distort. To control aphids, introduce natural predators such as ladybugs, prune infested leaves and stems, and apply insecticidal soap.
Spider Mites are tiny pests that feed on the plant's leaves, leaving behind a stippling pattern and webbing. To control spider mites, increase humidity around the plant, prune infested leaves, and apply a neem oil-based insecticide.
Caterpillars can chew on the plant's leaves, causing irregular holes and defoliation. To control caterpillars, handpick them off the plant and apply a biological insecticide containing Bacillus thuringiensis.
By implementing proper disease and pest management practices, you can ensure the healthy growth and development of your Strophanthus hispidus A. DC. plant.
