Origin
Vangueriella rhamnoides (Hiern) Verdc. is a plant species belonging to the family of Rubiaceae. The plant is found in Africa, specifically in Angola, Cameroon, Democratic Republic of Congo, Rwanda, Burundi, Kenya, Malawi, Mozambique, Tanzania, Uganda, Zambia, and Zimbabwe.
Common Names
The plant is commonly known as the Wild Medlar or African Medlar.
Uses
Various parts of the Wild Medlar plant have been used for medicinal purposes by traditional healers in its native region. The bark of the tree has been used to treat stomach ailments, fever, and venereal diseases. The roots have been used as a purgative and as a remedy for snakebites. The fruit of the plant is edible and has a tart taste, sometimes used for making jam or jelly.
Appearance
The Wild Medlar is a small to medium-sized tree that can grow up to 12 meters tall. The tree has a grayish-brown bark that is rough and fissured. Its leaves are simple, opposite, elliptic, and have a shiny green surface with a pale underside. The plant produces small, yellowish-white flowers that are arranged in terminal clusters. The fruit of the plant is orange to reddish-brown when ripe and is about 2-3 cm in size. The fruit has a fleshy pulp that surrounds a single seed.
Growth Conditions of Vangueriella Rhamnoides
Vangueriella Rhamnoides (Hiern) Verdc. is a rare and endangered plant species. It is native to tropical Africa and is found in countries such as Gabon, Cameroon, Congo, Angola, and Nigeria. The plant has specific growth conditions that must be met for optimal growth.
Light Requirements
Vangueriella rhamnoides is an understory plant that thrives in partial shade. The plant requires filtered sunlight or dappled shade for proper growth. Direct sunlight damages the delicate leaves and stunts the growth of the plant. In its natural habitat, Vangueriella rhamnoides grows under the canopy of tall trees that partially block the sun's rays.
Temperature Requirements
The plant can grow in temperatures ranging from 20-30°Celsius. However, it prefers temperatures around 23-25°Celsius. The plant can tolerate lower temperatures but growth may be slowed during this time. Frost and extended periods of cold weather harm the plant's leaves and stem.
Soil Requirements
Vangueriella rhamnoides requires well-drained soil with high organic matter. The soil pH must be slightly acidic, ranging from 5.5 to 6.5. The plant thrives in loamy soil that contains a mix of clay, sand, and silt. The soil must retain moisture while allowing excess water to drain out to avoid waterlogging. In the wild, Vangueriella rhamnoides grows in sandy soils near riverbanks and streams.
Cultivation Methods:
Vangueriella rhamnoides is an evergreen shrub that requires a well-drained and moist soil with partial shade to flourish. It grows well in tropical regions and can tolerate a wide range of soil conditions.
The best time to plant Vangueriella rhamnoides is during the rainy season, as it provides the plant with enough water to establish itself. The shrub can be propagated through seeds or stem cuttings, with the latter being the more efficient method.
Watering Needs:
Watering Vangueriella rhamnoides should be done regularly during the dry season to ensure it doesn't suffer from water stress. Overwatering should be avoided, as it can lead to root rot, which can destroy the entire plant.
Watering should be done in the early morning or late afternoon to prevent evaporation during hot periods when the sun is up. Ensure the soil stays moist but not waterlogged.
Fertilization:
Fertilization of Vangueriella rhamnoides should be done annually, using a balanced fertilizer rich in nitrogen, phosphorous, and potassium. The first application should be done six months after planting, and subsequent ones should be done annually during the rainy season.
Application should be done around the base of the plant, taking care not to apply too close to the stem. Overfertilization should also be avoided, as it can lead to the development of weak stems and foliage.
Pruning:
Pruning of Vangueriella rhamnoides is essential to maintain its shape and encourage bushy growth. Pruning should be done during the dry season, cutting back the stem by one-third of its length. Dead, damaged, and diseased branches should be removed at any time of the year.
The shrub can grow up to a height of 3 meters, so pruning should be done to control its height and spread. Care should be taken not to over-prune, as it can lead to stunted growth and reduced leaf and flower production.
Propagation of Vangueriella rhamnoides
Vangueriella rhamnoides, commonly known as Hiern, is propagated through various methods.
Seed propagation
Seeds of Vangueriella rhamnoides can be collected from healthy and matured fruits. The collected seeds should be cleaned and dried in a shaded area for a few days. The seeds can then be sown in a well-drained substrate in a shaded area. The substrate should be kept moist, and the germination should occur in a few weeks. The germinated seedlings can be transplanted to their permanent location once they are big enough to handle.
Cutting propagation
Cutting propagation is the most commonly used propagation method for Vangueriella rhamnoides. For this propagation method, stem cuttings of required length and diameter can be taken from healthy plants. The cuttings should be taken during the dormant season and treated with rooting hormone. The treated cuttings can be planted in well-drained soil or substrate in a shaded area. The substrate should be kept moist, and the rooted cuttings can be transplanted into their permanent location once they are stable.
Air layering propagation
Air layering is another propagation method that can be used for Vangueriella rhamnoides. For this method, a branch of the plant should be selected and a section of the bark should be removed. The exposed area should be treated with rooting hormone and wrapped with a moist substrate. The wrapped area should be covered with a transparent plastic sheet and securely fastened at both ends. The plastic sheet should be checked regularly for the growth of roots. Once the roots are formed, the rooted section can be cut away from the main plant and transplanted into its permanent location.
Disease Management
Vangueriella rhamnoides is susceptible to various diseases that could lead to yield reduction, distortion in seed germination, and death of the plant. The most common diseases that might affect this plant include:
- Root Rot: This is caused by fungi such as Fusarium spp. and Phytophthora spp. It is characterized by the rotting of the roots, leading to the wilting of the plant.
- Leaf Spot: This is caused by fungi such as Cercospora spp. and Alternaria spp. It leads to the formation of spots on the leaves, which could cause defoliation.
- Powdery Mildew: This is caused by fungi such as Erysiphe spp. and Sphaerotheca spp. It leads to the formation of a white powdery substance on the leaves and stems.
To manage these diseases, it is important to ensure that the plant is grown in well-drained soils, with proper spacing to allow for proper air circulation. Proper watering and fertilization should also be practiced to ensure that the plant is not stressed. The use of disease-resistant varieties is also advisable. Fungicides could also be used to manage these diseases.
Pest Management
There are various pests that might attack Vangueriella rhamnoides, making it necessary to implement proper pest management practices. The following are the pests that are commonly found:
- Mealybugs: These are sap-sucking insects that attack various parts of the plant, leading to stunted growth and deformation.
- Thrips: These are tiny insects that feed on the leaves, leading to silvering and distortion of the leaves and flowers.
- Aphids: These are sap-sucking insects that attack the tender parts of the plant, leading to stunted growth, deformation, and discoloration of the leaves.
Proper pest management practices including regular scouting for pests, maintaining a clean growing environment, and the timely use of pesticides is essential. Insecticides could be used while ensuring that the recommended safety measures are followed to prevent harm to the beneficial organisms.
