Overview of Olea europaea L. subsp. africana (Mill.) P.S.Green
Olea europaea L. subsp. africana (Mill.) P.S. Green, commonly known as African olive, is a plant species within the Oleaceae family. It is an evergreen tree that grows in warm, sunny climates and is endemic to the African continent. It is a subspecies of the Olea europaea species, which is widely known as the olive tree.
Description of Olea europaea L. subsp. africana (Mill.) P.S.Green
The African olive tree can grow up to 20 m tall and has a trunk diameter of up to 70 cm. Its bark is grayish-brown and smooth, while its leaves are opposite and lance-shaped, with a glossy, dark green upper surface and a pale, silvery-green lower surface. The plant has small, fragrant white flowers that bloom in the spring and produce small, edible, black fruits in the fall.
Common names of Olea europaea L. subsp. africana (Mill.) P.S.Green
The African olive tree is known by various names, depending on the region. Some of the most common names include:
- African olive
- Wild olive
- Olive plum
- Zwarte olyfboom (Afrikaans)
- Mkambati (Zulu)
- UmNga (Xhosa)
Uses of Olea europaea L. subsp. africana (Mill.) P.S.Green
The African olive tree has various uses and is highly prized for its medicinal and culinary properties. The tree's leaves contain compounds that have anti-inflammatory, antioxidant, and antimicrobial properties, making them useful for treating a variety of ailments, including infections, arthritis, and high blood pressure.
The fruit of the African olive tree is edible and is consumed fresh, dried, or pickled in many parts of Africa. The oil extracted from the fruit is also used for cooking and as a cosmetic ingredient. In addition, the wood of the tree is highly valued for its hardness and durability and is used for making furniture, utensils, and carvings.
Light Requirements
Olea europaea L. subsp. africana typically grows in full sunlight or partial shade. It needs at least 6 hours of direct sunlight each day to thrive. Lack of sufficient sunlight will result in poor growth and yield.
Temperature Requirements
This plant thrives best in warm climates with mild winters. A temperature range of 15-30°C (59-86°F) is considered ideal. Temperatures below 10°C (50°F) or above 40°C (104°F) can adversely affect growth and yield.
Soil Requirements
Olea europaea L. subsp. africana requires well-drained soil with a neutral to slightly alkaline pH (6.0-8.0). It prefers sandy loam soils that are rich in organic matter. The soil should not be waterlogged, as this can lead to root rot and poor growth. The plant is also tolerant to drought conditions.
Cultivation Methods for Olea europaea L. subsp. africana (Mill.) P.S.Green
Olea europaea L. subsp. africana (Mill.) P.S.Green, also known as African olive, is a slow-growing, highly drought-resistant plant that requires warm temperatures for optimal growth. It is recommended to plant African olive in well-drained soil that has a pH level between 5 and 8. The plant can grow in a wide range of soils, but it prefers sandy loam or clay loam soils. African olive also prefers full sun exposure for at least a few hours each day.
Propagation of African olive can be done through cuttings or seeds. Cuttings should be taken from the plant in the early spring or fall. Seeds should be planted in the fall or winter to allow for a full growing season. The plant can also be grafted onto rootstock for propagation.
Watering Needs for Olea europaea L. subsp. africana (Mill.) P.S.Green
African olive is highly drought-resistant and can survive in dry conditions. However, during the first year of growth, the plant should be watered regularly to establish a strong root system. Once established, African olive only needs to be watered during periods of drought or extended dry spells. It is important not to overwater the plant as it can lead to root rot.
Fertilization for Olea europaea L. subsp. africana (Mill.) P.S.Green
African olive does not require regular fertilization. If the plant is grown in poor soil, it may benefit from occasional fertilization with a balanced fertilizer. However, it is important not to over-fertilize the plant as this can lead to excessive growth and decreased fruit production.
Pruning Olea europaea L. subsp. africana (Mill.) P.S.Green
African olive should be pruned regularly to promote the growth of new branches and to shape the plant. Pruning should be done during the winter months when the plant is dormant. Dead or damaged branches should be removed, and the plant should be thinned to allow for better air circulation. Young plants should be pruned lightly to encourage branching and to shape the plant. Established plants can be pruned more heavily to control size and shape.
Propagation of Olea europaea L. subsp. africana (Mill.) P.S.Green
Olea europaea L. subsp. africana (Mill.) P.S.Green, commonly known as African olive, can be propagated through several methods:
Cuttings
Cuttings are the most common method of propagation for African olive. The best time to take cuttings is during late winter or early spring when the plant is dormant. Semi-hardwood cuttings 10-15 cm long can be taken from healthy mother plants. The cuttings should be treated with rooting hormones and planted in a well-draining soil mixture of sand, peat moss, and perlite. The cuttings should be kept in a humid environment, and once they start to show new growth, the humidity can be reduced and they can be gradually acclimated to regular outdoor conditions.
Seeds
African olive can also be propagated by seed. Seeds can be collected from mature fruit, which ripens in autumn. It's important to remove the flesh of the fruit and soak the seeds in water for 24 hours before planting. The seeds should be planted in a well-draining soil mixture at a depth of about 2 cm and kept moist. Germination can take up to six weeks, and it's important to protect the seedlings from direct sunlight and dry conditions.
Grafting
Grafting is a common propagation method for olive trees, including African olive. A scion (a piece of a desired plant) is taken from a healthy mother plant and grafted onto a wild olive rootstock. Grafting allows for quicker growth and fruit-bearing, but it requires more expertise than the previous methods mentioned.
Disease and Pest Management for Olea europaea L. subsp. africana (Mill.) P.S.Green
Olea europaea L. subsp. africana (Mill.) P.S.Green, also known as the African olive, is a moderately resistant plant to pests and diseases. However, it can still suffer from several issues that require attention to ensure optimal growth and yield. Here are some common diseases and pests that might affect the plant and ways to manage them:
Diseases
Bacterial Leaf Spot: This disease affects the plant's leaves, resulting in small, round, and water-soaked spots. The spots will turn yellow, then brown and develop a necrotic center. To manage this disease, prune the affected leaves and branches and avoid overhead watering. Use copper-based fungicides to prevent further infections.
Fungal Leaf Spots: If the plant's growing environment is humid and warm, fungal leaf spots can develop. The symptoms include circular or irregularly shaped brown spots with a yellow halo around them. To manage this disease, remove the infected leaves, and dispose of the debris. Use a fungicide to prevent further infections.
Verticillium Wilt: This disease is caused by soil-borne fungi that block the plant's vascular tissue, resulting in wilting and death. There is no cure for this disease, so prevention is crucial. Plant disease-resistant varieties, keep the soil pH balanced, and avoid overwatering the plant.
Pests
Olive Fruit Fly: This pest causes damage by laying its eggs inside the fruit, resulting in discolored and misshapen olives. To manage this pest, use sticky traps early in the season, and apply fruit fly baits according to label instructions.
Olive Lace Bug: This pest damages the plant's leaves by sucking the sap, resulting in yellow and distorted leaves. To manage this pest, prune the infested leaves and branches and use insecticidal soap or neem oil to control their population.
Black Scale Insects: These pests feed on the tree sap, causing yellowing, leaf drop, and stunted growth. To manage this pest, prune the affected parts and use horticultural oil or insecticidal soap.
In conclusion, monitoring the plant regularly for diseases and pests can help prevent significant damage and ensure healthy growth. Early identification and management of these issues are crucial for the plant's survival and yield. By following the suggested management practices, growers can keep Olea europaea L. subsp. africana (Mill.) P.S.Green healthy and thriving.
