Overview
Melasma calycinum (Hiern) Hemsl. is a perennial plant that belongs to the family Melastomataceae. It is native to tropical Africa and has various common names, including African Cowslip, Pink Spot, and Brasspin.
Appearance
Melasma calycinum has an erect and woody stem that can grow up to 1 m in height. The plant has simple, opposite leaves that are elliptic to ovate in shape and can grow up to 17 cm long and 10 cm wide. The leaves are dark green in color and have a smooth texture.
The flowers of Melasma calycinum are clustered at the terminal ends of the stems and have a bright pink or purple color. The flowers have five petals that are small and pointed and are arranged in a radial pattern.
Uses
Melasma calycinum is used for various medicinal purposes in African traditional medicine. The plant's leaves and roots are used to treat various ailments, including respiratory diseases, stomach problems, and fever. The leaves are also boiled or infused to make a tea that is believed to have a mild sedative effect.
Melasma calycinum is also used as an ornamental plant in gardens and landscape designs.
Cultivation
Melasma calycinum prefers moist, well-drained soils and thrives in full sunlight. The plant is propagated through cuttings or seeds and requires regular watering to support its growth. It is a low-maintenance plant and requires minimal pruning to maintain its shape and promote healthy growth.
Growth Conditions for Melasma calycinum (Hiern) Hemsl.
Melasma calycinum (Hiern) Hemsl., commonly known as African violet, is a perennial plant belonging to the family Melastomataceae. This plant is widely cultivated as an ornamental plant due to its attractive, bright purple to blue flowers that appear in clusters. To ensure healthy growth of the African violet, the following are the ideal growth conditions:
Light
Melasma calycinum (Hiern) Hemsl. grows best in bright, indirect sunlight, so it's essential to place the plant near a window covered with sheer curtains or a north-facing window. When exposed to direct sunlight, the leaves may burn and turn yellow.
Temperature
The optimal temperature range for the African violet is between 18-25°C (65-77°F) during the day and 15-18°C (59-65°F) at night. Temperatures above 30°C (86°F) can cause the leaves to wilt and may even kill the plant. On the other hand, temperatures below 10°C (50°F) can cause the leaves to turn yellow and black.
Soil Requirements
Melasma calycinum (Hiern) Hemsl. requires well-draining, crumbly, and humus-rich soil that retains moisture without becoming waterlogged. Ideally, a combination of peat moss, perlite, and vermiculite is the best soil mix. The pH should be between 6.0 and 7.0 for optimal growth.
Following these growth conditions will ensure that Melasma calycinum (Hiern) Hemsl. will thrive and produce beautiful flowers for an extended period.
Cultivation Methods
Melasma calycinum, commonly known as the African violet, is a small, herbaceous plant that is relatively easy to cultivate. The plant can be grown either in containers or planted directly in the garden soil.
You can start by choosing a spot with well-draining soil that has partial to full shade. The ideal temperature for the plant is between 60°F and 85°F. The soil pH should range from slightly acidic to neutral (5.5 to 7.0).
The plant can also be propagated by dividing the root ball or taking cuttings from healthy plants. Once planted, it takes about three to four weeks for the plant to adapt to the new environment.
Watering Needs
Melasma calycinum prefers moist soil that is neither too dry nor too wet. Overwatering can lead to root rot, while insufficient watering can lead to stunted growth and dryness. It is recommended to water the plant once or twice a week, depending on the humidity of the environment.
Watering should be done in the morning or late afternoon, and water should not be allowed to touch the leaves as it can cause fungal growth. The plant should also be misted regularly to increase humidity around it.
Fertilization
To ensure healthy growth and blooming, Melasma calycinum requires regular fertilization. A balanced, water-soluble fertilizer with equal amounts of nitrogen, phosphorus, and potassium is ideal for the plant.
Fertilization should be done every four to six weeks during the growing season, which is from spring to fall. During the winter months, fertilization can be reduced or stopped altogether.
Pruning
Melasma calycinum requires minimal pruning as it has a compact shape. However, occasional trimming of the leaves and flowers can be done to promote bushier growth and flowering.
Deadheading, which involves removing the old flowers, should be done regularly to encourage the plant to produce new blooms. Any wilting or yellowing leaves should also be removed to prevent the spread of diseases.
Propagation of Melasma calycinum (Hiern) Hemsl.
Melasma calycinum (Hiern) Hemsl. can be propagated through both sexual and asexual methods.
Seed propagation
Seeds of Melasma calycinum can be sown directly into well-drained soil in a greenhouse or nursery bed. The optimum time for sowing seeds is during January to March when the weather is favourable. The seedbed should be watered regularly to maintain optimal moisture levels. Germination usually occurs within 30-45 days of sowing the seeds.
Vegetative propagation
Melasma calycinum can also be propagated through vegetative methods such as stem cuttings and division.
Stem Cuttings
Stem cuttings, approximately 10 cm in length, can be taken from a healthy plant during the spring or early summer season. The cuttings should be dipped in rooting hormone and inserted into a pot filled with a mix of peat and sand. The pot should be placed in a warm, humid environment to encourage root growth. Transplanting can be done once the roots have established.
Division
Division is another method of propagating Melasma calycinum, which involves dividing the root system of an existing plant into multiple sections. The divided sections should have an adequate number of shoots and roots. Each section should be planted into a separate container or directly into the ground. The best time for division is during the early spring or fall when the plant is not actively growing.
Disease Management
One of the common diseases that affect Melasma calycinum is leaf spot caused by the fungus Cercospora. This fungus can cause brownish-purple spots on the leaves, leading to leaf yellowing, drying, and dropping. Application of fungicides, such as chlorothalonil and copper-based fungicides, can help to control the disease. As a preventive measure, it is advisable to avoid watering the foliage and instead, apply water around the plant's base.
Another disease problem is powdery mildew, which is caused by the fungal pathogen Erysiphe cichoracearum. Powdery mildew can cause a white powdery coating on the leaves, making them look unsightly and negatively affecting plant growth. Good air circulation around the plant and proper spacing can help to reduce the incidence of powdery mildew. Alternatively, applying fungicides such as sulfur or neem oil can help to control the disease.
Pest Management
The principal insect pest that infest Melasma calycinum is the spider mites. These pests are prevalent during hot, dry weather conditions, and they can cause leaves to turn yellow, dry up and ultimately lead to defoliation. The use of predatory mites, such as Phytoseiulus persimilis, can help control spider mites. Alternatively, spraying the plant with insecticidal soap or neem oil can also help manage spider mites. It is important to note that chemical insecticides can disrupt the natural balance of the ecosystem, leading to even more pest problems.
