Overview
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata (Engl.) Chiov. is an evergreen tree that belongs to the Anacardiaceae family. It is commonly found in the southern, eastern, and central parts of Africa. The plant is characterized by its shiny leaves, fluffy flowers, and bright red fruits.
Common Names
The plant is commonly known by several names, including the Natal red star apple, the bird plum, the African wild plum, and the mukalati. In Swahili, it is called Muvula.
Uses
The Rhus natalensis tree has several commercial and medicinal uses. Its fruits are edible and used in the production of traditional African alcoholic drinks. The fruits are also consumed by birds and monkeys. The plant's bark, roots, and leaves are used to treat various ailments such as diarrhea, dysentery, and respiratory tract infections. Additionally, the wood from the tree is used for carving and making furniture.
General Appearance
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata (Engl.) Chiov. is an evergreen tree that can reach a height of up to 20 meters. The plant has a dense and rounded crown, with smooth gray bark. It produces shiny, leathery leaves that are obovate in shape, with a pointed tip and a tapering base. The leaves are 8-15 cm long and 5-10 cm wide. The plant also produces small yellow flowers that are arranged in fuzzy, dense clusters. The flowers are followed by bright red, spherical fruits that are about 1 cm in diameter.
Light requirements
Rhus natalensis var. obovatifoliolata grows well in areas with plenty of sunlight. It thrives in full sun, and it is advisable to plant it in areas with exposure to at least 6 hours of sunlight per day. Lack of enough sunlight results in weak and spindly growth.
Temperature requirements
This plant grows in a wide range of temperatures. It prefers warm, humid climates but can also thrive in cold weather. The temperature range for this plant is between 10°C (50°F) and 30°C (86°F). However, during the dormant period, the plant can withstand lower temperatures.
Soil requirements
This plant can grow in a variety of soils, but it favors sandy soils that are well-drained. It cannot withstand waterlogged soils and prefers medium to low fertility soils. The soil pH should be slightly acidic, ranging from 5.5 to 7.0. It is advisable to add organic matter, such as compost, to improve soil moisture retention and fertility.
Cultivation methods
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata (Engl.) Chiov., commonly known as Natal currant, is a low-maintenance, evergreen shrub that can grow up to 3 m high. It prefers warm, dry climates and sandy or rocky soils and can tolerate drought conditions. Natal currant can be propagated by seed or cuttings, preferably in spring or early summer. Seedlings should be planted in well-draining soil in a sunny location.
Watering needs
Once established, Natal currant is a drought-tolerant plant and requires little watering. However, regular watering during the growing season (spring to autumn) can encourage growth and protect against heat stress. Water should be applied at the base of the plant and not on the leaves to avoid fungal diseases.
Fertilization
Although Natal currant does not require frequent fertilization, applying a slow-release fertilizer in spring can improve growth and blooming. A high-nitrogen fertilizer should be avoided as it can result in excessive growth at the expense of flowering.
Pruning
Natal currant does not require regular pruning, but it can be beneficial to remove dead or diseased branches and promote bushier growth. Pruning can be done in late winter or early spring before new growth starts. It is important to use sharp, clean pruning shears to prevent damage to the plant.
Propagation of Rhus natalensis Bernh. ex Krauss var. obovatifoliolata
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata (Engl.) Chiov. can be propagated using different methods, including:
Seed Propagation
The easiest and most common method to propagate Rhus natalensis Bernh. ex Krauss var. obovatifoliolata is through seed propagation. The seeds should be collected when they are ripe and placed in cold water for up to 24 hours to remove the fruit pulp. Afterward, the seeds can be air-dried and stored in a dry and cool place until they are ready to be sown.
The sowing should be done in well-drained soil in seedling trays or pots with a mixture of sand and compost. The seeds should be covered by a thin layer of soil and watered. Germination should occur within 2-3 weeks.
Cutting Propagation
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata can also be propagated through cuttings. Semi-hardwood cuttings, taken during the summer season, should be used; these should include a bark piece and one or two leaves. The cutting should be dipped in rooting hormone powder and placed in a well-drained potting mix. The pot should be covered with a plastic bag to retain moisture and should be retained in a shaded area until roots are formed.
Division Propagation
Propagation by division is another way to propagate Rhus natalensis Bernh. ex Krauss var. obovatifoliolata. This method involves dividing an existing plant into multiple parts and planting them in new locations.
The process of division should be carried out when the plant is dormant, this is, during the winter season. The plant should be gently lifted from the soil and the roots and stem should be separated using a sharp, clean knife. The separated parts should be planted in separate containers or a new location in the garden.
Disease Management
Rhus natalensis Bernh. ex Krauss var. obovatifoliolata (Engl.) Chiov., commonly known as the Natal sour plum, is typically resistant to many pests and diseases. However, some diseases can still affect it, such as:
- Anthracnose: This fungal disease causes small, dark spots on leaves, which can eventually grow larger and merge. In severe cases, it can cause extensive defoliation and premature death. To manage anthracnose, infected debris should be removed and destroyed, and fungicidal sprays may be applied during the growing season.
- Leaf spot: Leaf spot is a common fungal disease that affects the leaves of Rhus natalensis. It causes small, circular or irregular brown spots on the leaves. The affected leaves will turn yellow and fall off, leading to defoliation and reduced vigor. To control leaf spot, remove infected leaves and branches promptly, and use proper sanitation to avoid the spread of the fungus.
Pest Management
Rhus natalensis is relatively pest-resistant, but some pests may still cause problems. Here are some common pests that affect Natal sour plum and the ways to manage them:
- Mites: Mites are a common pest that can feed on the leaves and tender plant parts. Heavy infestations can cause the leaves to discolour, curl and drop. To manage mites, use a high-pressure water spray to dislodge them, or use an insecticidal soap or miticide if necessary.
- Caterpillars: Caterpillars can feed on the leaves and weaken the plant. Hand picking is an effective method of control for small populations, but insecticides may be necessary in severe cases.
- Scale Insects: Scale insects can sap the life out of the plant by sucking sap from the leaves and branches. They can lead to yellowing of leaves, stunted growth and leaf drop. To manage scale insects, prune out affected branches and control ants that may be farming the scales. Insecticides may be required in severe infestations.
By following these management techniques for pests and diseases, growers can ensure the Natal sour plum plants have fewer obstacles to producing a healthy crop.
