Introduction
Coleus glandulosus Hook.f. is a plant that belongs to the family Lamiaceae. It is a perennial herb known for its unique leaf patterns and is native to the Himalaya region.
Common Names
The plant is commonly known as the Sticky Coleus due to the presence of glandular hairs on the stem and leaves. Other common names include Indian Coleus, Boldo Coleus, and Giant Coleus.
Appearance
The plant grows up to a height of 60 to 90 cm. The leaves are opposite, ovate, and have serrated margins. The leaf color is dark green, with reddish-purple veins and blotches. The inflorescence is a panicle of small blue or purple flowers.
Uses
The plant is widely used in traditional medicine for its medicinal properties. The leaves are rich in forskolin, a substance that has been found to regulate several biological processes in the body. It is used to treat asthma, glaucoma, and other ailments. In addition, the plant is a popular ornamental plant due to its attractive leaf patterning and is commonly used in gardens, containers, and indoor settings.
Light Requirements:
Coleus glandulosus Hook.f. is an indoor and outdoor plant that prefers bright indirect sunlight. It is important to protect it from direct sunlight, especially during the hot summer months as it may cause leaf scorching.
Temperature Requirements:
This plant prefers to grow in warm temperatures. The ideal temperature range for the Coleus glandulosus Hook.f. is between 18 and 27 °C. It is important to avoid placing the plant in drafty areas as it may lead to loss of foliage or stunted growth.
Soil Requirements:
The Coleus glandulosus Hook.f. plant prefers moist and well-draining soil. It can thrive in different types of soil, including loam, sandy, or clay soil. However, it is important to ensure that the soil pH is between 6.0 and 7.5. If soil pH levels are not optimal, it may affect the uptake of nutrients, leading to stunted growth and poor flowering.
Cultivation of Coleus glandulosus Hook.f.
Coleus glandulosus Hook.f. is a perennial plant that is primarily grown as a decorative plant for indoor and outdoor settings. It is relatively easy to grow and care for.
The plant prefers well-drained soil with a slightly acidic pH between 6.2 to 6.8. While the plant can tolerate full sunlight, it grows better in partially shaded areas with at least 4 to 6 hours of sunlight.
Coleus glandulosus Hook.f. can be propagated through stem cuttings. The cuttings should be taken from the plant's stem and placed in a well-drained potting mix with high organic matter content. The potting mix should be kept moist, and the cuttings should be placed in a warm and humid environment until they root.
Watering Needs
Coleus glandulosus Hook.f. requires moderate watering and should not be overwatered as it can lead to root rot. The soil should be allowed to dry slightly between watering sessions. The amount and frequency of watering will depend on the weather, humidity levels, and plant size.
It is recommended to water the plant in the early hours of the day to prevent any fungal growth. The plant also benefits from periodic misting, particularly during hot and dry months.
Fertilization
Coleus glandulosus Hook.f. benefits from regular fertilization as it helps maintain the plant's bright foliage and promotes growth. The plant should be fertilized during the growing period, preferably every two weeks, using a balanced fertilizer with an NPK ratio of 20-20-20 or 10-10-10.
Over-fertilization should be avoided as it can cause leaf-burn, stunted growth and soil toxicity. Plants grown indoors require less fertilization compared to outdoor plants.
Pruning
Coleus glandulosus Hook.f. benefits from regular pruning, which helps maintain its shape and encourages bushy growth. Pruning is best done during the growing period and should be performed using sharp and sterilized cutting tools.
To prune the plant, remove the soft growing tips at the top of the plant and cut the long and leggy stems to encourage bushy growth. The plant's dead or yellowing leaves should also be regularly removed to maintain its bright foliage.
Pruning also helps control the plant's height and size, making it an ideal plant for small spaces like balconies and patios.
Propagation of Coleus Glandulosus Hook.f.
The Coleus glandulosus Hook.f. can be propagated through different methods such as seed propagation, cutting propagation, and tissue culture.
Seed Propagation
The plant's seeds can be sown directly into the soil during the spring or summer when temperatures are warm enough for germination to occur. Sow the seeds on top of the soil and press them down gently to ensure they make good contact with the soil.
It's important to keep the soil moist and in a warm place. The seedlings will usually start emerging in two to three weeks. Once the seedlings have grown to a size big enough to handle, they can be transplanted to larger pots or directly outdoors into the garden.
Cutting Propagation
Cutting propagation is another easy and effective method for growing Coleus glandulosus Hook.f. This method involves taking a stem cutting from a mature plant and planting it in soil to regrow new roots.
To take a cutting, select a healthy stem with at least two sets of leaves. Use a sharp and clean knife or scissors to cut the stem at an angle just below the node. Remove the bottom leaves and dip the cut end into rooting hormone powder before placing it into soil.
After planting, keep the soil moist and in a warm place, and the new roots will start to appear in a few weeks. Once the plant has established strong roots, it can be transplanted to a larger pot or outside into the garden.
Tissue Culture Propagation
Tissue culture propagation is a more complicated method of propagation that involves growing the plant from a small tissue sample in a sterile laboratory environment. This method is typically used for plant breeding or mass production of plants.
In tissue culture propagation, the plant cells are grown in a nutrient-rich medium under controlled conditions. The growing cells are then transferred to a new medium and separated into individual plantlets before being transplanted in soil.
While tissue culture propagation is more complicated, it allows for the production of large numbers of identical plants from a small sample, making it ideal for commercial plant production.
Disease and Pest Management for Coleus Glandulosus Hook.f.
Coleus glandulosus Hook.f. is a beautiful perennial plant that is grown for its attractive foliage and colorful leaves. However, like other plants, Coleus glandulosus Hook.f. is susceptible to diseases and pests. Here are some common diseases and pests that might affect this plant:
Diseases
1. Leaf Spot: Leaf spot on Coleus glandulosus Hook.f. is caused by a fungal infection that causes irregular brown spots with yellow margins on the leaves. The fungus thrives in wet and humid conditions. To manage leaf spot, remove and destroy any infected leaves, provide proper air circulation, and avoid over-watering the plant.
2. Powdery Mildew: Powdery mildew is a common fungal disease that appears on the upper surface of the leaves. The disease causes a powdery white coating, which eventually turns black and causes the leaves to wither and die. To prevent powdery mildew, avoid overhead watering, provide good air circulation, and remove any infected leaves immediately.
3. Bacterial Blight: Bacterial blight is a bacterial infection that causes water-soaked lesions on the leaves and stems of the plant. The infection spreads rapidly in humid conditions. To manage bacterial blight, remove and destroy any infected plant parts and avoid over-watering the plant.
Pests
1. Aphids: Aphids are small insects that feed on the sap of the plant, causing the leaves to curl and eventually die. To manage aphids, spray the plant with a strong jet of water, or use insecticidal soap or neem oil.
2. Whiteflies: Whiteflies are tiny insects that suck the sap of the plant and cause yellowing and wilting of the leaves. To manage whiteflies, use yellow sticky traps to attract and trap them, or spray the plant with insecticidal soap or neem oil.
3. Spider Mites: Spider mites are tiny, red or brown insects that feed on the underside of leaves, causing yellowing and mottling of the leaves. To manage spider mite infestations, spray the plant with a strong jet of water, use neem oil or insecticidal soap, or introduce predatory mites to control their population.
By practicing proper care and vigilance, you can easily prevent and manage diseases and pests on your Coleus glandulosus Hook.f. plant, ensuring its longevity and vigor.
