Overview
Coleus welwitschii Briq. is a tropical perennial plant species native to Africa. It is a member of the Lamiaceae family and is closely related to the more common Coleus scutellarioides, also known as the painted nettle or coleus. In its native region, this plant is known by different common names such as 'Shakambantu' in Zambia, 'Kaani' in Uganda, and 'Nyogolo' in Tanzania.
Physical Description
The leaves of Coleus welwitschii Briq. are elongated to ovate, fleshy, and have serrated margins. The leaf blades are up to 10 cm long and 8 cm wide and have a slightly undulate surface. They are olive green with prominent veins on the upper side and purple underneath. The stem is approximately 70 cm in length, thin, and green in color. The flowers are small, purple, and arranged in whorls at intervals along the stem. They bloom in clusters at the end of the stem and have a mild fragrance.
Uses
Coleus welwitschii Briq. has several traditional medicinal uses in its native region. The leaves are used to treat numerous ailments, including fever, headaches, toothaches, and stomach disorders. The plant's extracts also have anti-inflammatory and analgesic properties. In Zambia, the plant is believed to have aphrodisiac effects, and a leaf decoction is taken to improve sexual performance. In addition to its medicinal uses, the plant is also grown as an ornamental, and its striking foliage adds color and texture to gardens or as a houseplant.
Cultivation
Coleus welwitschii Briq. prefers a well-draining soil with a slightly acidic to neutral pH. The plant requires ample moisture but can't tolerate soggy soil. It thrives in partial shade, but some direct sunlight is necessary for optimal growth. Propagation can be done using stem cuttings, which should be taken during the growing season. Coleus welwitschii Briq. can be propagated through seed as well, but it may take longer for the plant to reach maturity. Pests and diseases are not major concerns, and the plant is relatively easy to maintain.
Typical Growth Conditions for Coleus welwitschii Briq.
Coleus welwitschii Briq. is a tropical plant native to Angola, Africa. It is a member of the Lamiaceae family, commonly known as the mint family. This plant has a unique leaf coloration with shades of green, yellow, orange, and red. Below are the typical growth conditions for Coleus welwitschii Briq.
Light Requirements
Coleus welwitschii Briq. needs a bright but indirect light for optimal growth. Direct sunlight can scorch the leaves and cause them to wither. Therefore, it is best to place the plant near a window where it can receive filtered light or under a shade. Artificial light can also be used, but it should be placed at a distance of about one meter from the plant to provide the correct amount of light.
Temperature Requirements
As a tropical plant, Coleus welwitschii Briq. requires warm temperatures to thrive. The ideal temperature range for the plant is between 18°C to 30°C (64°F to 86°F). Temperatures below 10°C (50°F) can cause damage to the plant and lower growth rates. Therefore, it is important to keep the plant indoors or in a greenhouse where the temperatures are optimal.
Soil Requirements
Coleus welwitschii Briq. requires well-drained soil rich in nutrients. The soil should be slightly acidic with a pH range of 6.0 to 6.5. The plant prefers loose, sandy, or loamy soil with good water retention and proper aeration. A good mix of peat moss, perlite, and vermiculite can provide the necessary soil structure for the plant to grow. It is important to avoid waterlogging and allow the soil to dry slightly before the next watering.
Cultivation Methods
The Coleus welwitschii Briq., also known as the Welwitsch's coleus, is a lovely plant to grow indoors or outdoors. It is a subtropical plant that flourishes best in warm, humid environments. To grow this plant effectively, consider the following:
- The soil should be a well-draining mix of peat moss, sand, and loam at a pH of 6.0-7.5
- Plant your coleus in a partly shaded position with at least 4-6 hours of indirect sunlight per day
- Keep the temperature between 60°F - 85°F (16°C - 29°C)
- It's a good idea to trace from stem cuttings, laying them on the soil surface and covering them gently with soil. Apply a rooting hormone for increase chances of sprouting.
Watering Needs
Coleus welwitschii Briq. plants require regular watering and do not like to go without water for long periods. However, overwatering may lead to root rot. Follow the tips below to ensure your plant stays hydrated:
- Water your plant regularly enough to keep the soil moderately moist but not waterlogged.
- Do not allow water to pool in the soil or saucer underneath the pot, as it may lead to root rot.
- Ensure the water you use is at room temperature, as cold water may harm the foliage and roots.
- It's best to water in the morning to reduce the potential for wet leaves during the night which can cause fungus.
Fertilization
Coleus welwitschii Briq. plants are light to average feeders, and notably benefit from regular fertilization. Consider the following when feeding your plant:
- Use a balanced liquid fertiliser every two weeks, ideally throughout spring, summer, and autumn
- Avoid over-fertilization as it can cause weak growth and damage to roots.
- Remember to always follow the instructions on the fertiliser packaging with precision.
Pruning
Coleus welwitschii Briq. plants are generally low-maintenance in pruning. Follow the tips below to make sure you're doing it right:
- Pruning isn’t necessary but improve the look of the plant if you happen to cut off lanky or sprawling growths.
- If you're growing coleus indoors, it may become leggy if it’s not getting enough light, and pruning can help give it back the bushy appearance.
- Trim excess branches of parallel pairs of the stem to the nearest node.
- Don't discard the plant trimmings or prunings as you can use them as cuttings to propagate new coleus plants with.
Propagation of Coleus welwitschii Briq.
Coleus welwitschii Briq., also known as the velvet coleus, is a tropical plant that is commonly used as an ornamental plant due to its attractive foliage. Propagation of this plant is relatively easy and can be achieved by several methods. These methods include:
Seeds
Propagation by seeds is the easiest and most common method of propagating velvet coleus. Seeds should be collected from the plant during the summer and sown in a well-draining soil mix. The soil should be kept moist and placed in a warm and bright area. Seed germination usually occurs after 14-21 days. Once the seedlings have grown at least four sets of true leaves, they can be transplanted into individual pots.
Cuttings
Coleus welwitschii can also be propagated from stem cuttings. Cuttings should be taken from healthy and vigorous plants and should be around 4-6 inches long. Cuttings should be taken in the spring or summer and should be planted in a well-draining soil mix. The soil should be kept moist and placed in a warm and bright area. Rooting usually occurs after 2-3 weeks. Once the cuttings have established roots, they can be transplanted into individual pots.
Division
Propagation of velvet coleus by division involves dividing an existing plant into smaller sections and planting them in individual pots. This method is usually recommended for older plants that have become too large or woody. To propagate by division, carefully remove the plant from its pot and separate the root ball into several smaller sections. Each section should have several stems and roots. The new sections should be planted in a well-draining soil mix and kept moist until they have established roots.
Disease Management
Coleus welwitschii Briq. is susceptible to various foliar and stem diseases, including fungal leaf spots and stem rot. These diseases affect the plant's overall health and appearance. To manage these diseases, it's important to maintain proper plant hygiene by removing and destroying any infected plant parts. Additionally, avoid overhead watering and ensure good air circulation. Fungicides may also be used as a preventive measure but should only be applied following label instructions.
Pest Management
Several pests can attack Coleus welwitschii Briq., including thrips, spider mites, and whiteflies. These insects feed on the plant's tissue, causing yellowing, stunted growth, and distortion. To manage these pests, regularly inspect the plant for signs of infestation and use biological controls such as releasing natural predators or applying neem oil. Additionally, small infestations can be controlled with insecticidal soap or horticultural oil, but ensure that the product is safe to use on the plant.
