Origin
The Coleus schweinfurthii Baker is a tropical plant species that belongs to the family Lamiaceae. This plant species is commonly found in East Africa, particularly in the countries of Kenya, Tanzania, and Uganda.
Common Names
The Coleus schweinfurthii Baker is also known by several other names such as the Schweinfurth's Coleus and the Tanzanian Coleus. In the Swahili language, this plant is referred to as 'Muare.'
Uses
The Coleus schweinfurthii Baker has several practical uses. In traditional East African medicine, the plant is often used for treating various ailments such as stomach upsets, fever, and respiratory diseases. The plant's roots are also used for their antibacterial properties. The Tanzanian Coleus is also cultivated as an ornamental plant and is commonly planted in gardens and along pathways for its attractive foliage and vibrant colors.
General Appearance
The Coleus schweinfurthii Baker is a perennial plant that grows up to two meters high. It has a woody base, and its stems are covered with short hairs. The leaves are thick, ovate, and have a velvety texture with a green to purple coloration. The edges of the leaves are serrated, and the plant produces small, purple flowers. Additionally, the plant has a distinct fragrance that is released when the foliage is touched or bruised.
Light Requirements
Coleus schweinfurthii Baker requires moderate to bright, indirect light. It should be kept in a spot where it can receive at least 4-6 hours of sunlight daily, but not in direct sunlight as it may cause the leaves to scorch. In areas with insufficient natural light, artificial lighting can be provided to supplement the plant's needs.
Temperature Requirements
It thrives in temperatures between 18°C-25°C, however, it can tolerate temperatures as low as 10°C(the minimum) without causing much damage. Coleus schweinfurthii Baker should be kept away from drafts and sudden temperature changes, which can cause the leaves to droop and damage the plant.
Soil Requirements
The plant prefers well-draining and fertile soil. A good potting mixture can be made with equal parts of perlite, vermiculite, and peat moss. It also likes soil that is slightly acidic with a pH between 6.5 and 7.5. Providing organic matter such as compost or dried manure can aid in the growth of the plant.
Cultivation
The Coleus schweinfurthii Baker plants can be propagated by cuttings, seeds, or stem layering. Stem cuttings can be taken in the spring or summer, around 10 cm long, and inserted in damp soil or water until roots appear. They can then be transferred into pots and grown indoors or in greenhouses. For outdoor planting, seeds can be sown on a well-prepared seedbed in spring or early summer, lightly covered with soil, and kept moist until germination.
Watering Needs
Coleus schweinfurthii Baker plants need regular watering. The frequency depends on environmental conditions, such as temperature, humidity, and soil moisture. In general, the plants require moist soil but not waterlogged. It is recommended to water them deeply once or twice a week or as needed, depending on the soil's moisture level. Overwatering can lead to root rot and fungal diseases, while underwatering can cause the leaves to wilt and drop.
Fertilization
Proper fertilization is crucial for healthy growth and vibrant foliage of Coleus schweinfurthii Baker plants. A balanced fertilizer with equal parts nitrogen, phosphorus, and potassium is ideal. Fertilize the plants every two weeks during the growing season, spring through fall. Avoid overfeeding, as it can cause excessive growth, leggy stems, and loss of leaf coloration.
Pruning
Pruning can help Coleus schweinfurthii Baker plants maintain their shape, promote bushier growth, and prevent legginess. Deadhead or pinch off the flowers as soon as they appear to divert energy into foliage production. Pinch the tips of the stems to stimulate branching and denser growth. Trim the stems back by one-third to half their length in early summer to encourage fuller growth and prevent flopping. Remove any damaged or diseased leaves and stems promptly to prevent the spread of infections.
Propagation of Coleus schweinfurthii Baker
Coleus schweinfurthii Baker can be propagated through various methods that include:
Seeds
Seeds are the most common method of propagation for Coleus schweinfurthii Baker. To propagate the plant from seeds, harvest seeds from the parent plant and sow them in a well-drained potting mix. Keep the soil moist and place the pot in a warm, well-lit location. Germination usually occurs within two weeks.
Stem cuttings
Stem cuttings are another effective method of propagating Coleus schweinfurthii Baker. Take stem cuttings from healthy parent plants that are about 4-6 inches long. Remove all the leaves from the lower half of the cutting and plant them in a well-draining potting mix. Keep the soil moist and place the pot in a warm, well-lit location. The cutting should start to root in about two to three weeks, and new growth should appear within four weeks.
Division
Division is the most straightforward method of propagation of Coleus schweinfurthii Baker, but it requires an already existing plant. Gently remove the plant from its container and separate the individual clumps. Repot the separated clumps in a well-draining potting mix and keep the soil moist.
Disease and pest management for Coleus schweinfurthii
Coleus schweinfurthii Baker is a beautiful, durable, and low-maintenance plant. However, like any other plants, it is also susceptible to diseases and pests. Here are the most common diseases and pests that might affect Coleus schweinfurthii and suggested ways to manage them:
Diseases
Bacterial blight - It is a common disease that causes blackened stems and leaves, wilting, and leaf drop. The best way to manage bacterial blight is to remove and destroy infected plants or plant parts. Use a fungicide to treat the remaining plants.
Downy mildew - It is a fungal disease that causes yellowing, curling, and distortion of leaves, as well as a grayish-white downy growth. Remove and destroy infected plant parts and use a fungicide to treat the remaining plants. Avoid overhead watering to prevent the spread of downy mildew.
Root rot - It is a fungal disease that causes the plant to wilt, yellow, and eventually die. Overwatering, poor drainage, and contaminated soil are common causes of root rot. Improve drainage, allow the soil to dry out between watering, and avoid overwatering to prevent root rot.
Pests
Spider mites - They are common pests that cause yellowing, stippling, and webbing on leaves. Use insecticidal soap or neem oil to kill spider mites. Keep the plants well-hydrated to deter infestations.
Mealybugs - They are soft-bodied insects that feed on plant sap and cause yellowing, distortion, and stunted growth. Use insecticidal soap or neem oil to kill mealybugs. You can also use a cotton swab dipped in rubbing alcohol to remove them from the plant.
Aphids - They are small, pear-shaped insects that feed on the new growth of the plant and transmit viruses. Use insecticidal soap or neem oil to kill aphids. Ladybugs and lacewings are natural predators of aphids and can be used to control their population.
Regular inspection and maintenance of the plants can prevent these diseases and pests from getting out of hand and protect the health and vitality of Coleus schweinfurthii Baker.
