Origin
Calvoa rosularis Gilg ex Engl. is a plant species that belongs to the family Melastomataceae. It is native to Sub-Saharan Africa, specifically in the countries of Angola, Cameroon, Congo, Democratic Republic of Congo, Equatorial Guinea, Gabon, Nigeria and Uganda.
Common Names
Calvoa rosularis Gilg ex Engl. has various common names such as the African melastome, dwarf melastome, and the Congo violet.
Uses
The plant has several uses in traditional medicine. Its leaves and roots are known to have antioxidant and anti-inflammatory properties and are used to treat a range of ailments such as fever, diarrhea, and stomach pains. It has also been studied as a potential treatment for diabetes.
In addition to its medicinal properties, Calvoa rosularis Gilg ex Engl. is a popular ornamental plant due to its striking appearance. It is commonly used in landscaping, either as a standalone plant or as part of a mixed border.
General Appearance
Calvoa rosularis Gilg ex Engl. is a perennial shrub that typically grows to about 30-60 cm in height. Its leaves are arranged in a rosette at the base of the stem, and are green in color with a slightly textured surface. The plant produces small, pink-purple flowers that are clustered at the top of the stem. The fruit is a small, white berry that contains several seeds.
The plant prefers moist, well-draining soils and partial to full shade. It is a hardy plant that requires minimal care, making it an excellent choice for beginners or for those who want to add a splash of color to their garden without much effort.
Light Requirements
The Calvoa rosularis Gilg ex Engl. plant thrives in bright, indirect light. It is crucial to protect it from direct sunlight as it burns the leaves and may cause the plant to suffer from heat stress.
Temperature Requirements
Calvoa rosularis Gilg ex Engl. thrives in warm temperatures, but avoid temperatures that exceed 90°F (32°C) as it may cause the plant’s leaves to wither and drop. Ideally, maintain a temperature of 60°F (16°C) to 85°F (29°C) which is considered optimal growth temperature for the plant.
Soil Requirements
The Calvoa rosularis Gilg ex Engl. plant thrives in well-draining and fertile soil. The soil should contain an equal mixture of sand, peat, and a little bit of perlite. Make sure the soil’s pH level is between 6.0 and 7.0. Remember to avoid constantly waterlogged soils and instead, allow the soil to dry halfway down before watering the plant.
Cultivation Method for Calvoa rosularis Gilg ex Engl.
Calvoa rosularis Gilg ex Engl. is an epiphytic plant, which means that it grows on trees. It is indigenous to Central and South America. To cultivate Calvoa rosularis, you should consider its natural habitat. The plant grows in moist and shady environments, which means it needs to be in a location with low sunlight and high humidity. Before you plant Calvoa rosularis, make sure its location has a high level of humidity and is well-ventilated.
Watering Needs for Calvoa rosularis Gilg ex Engl.
Calvoa rosularis Gilg ex Engl. needs to be frequently watered to survive, but it also requires good drainage to prevent root rot. It is recommended to water the plant when the soil feels dry to the touch. You can use rainwater or distilled water instead of tap water because tap water may contain chemicals or minerals that could harm the plant. Water the plant from above and let the water drain out from the bottom of the pot.
Fertilization for Calvoa rosularis Gilg ex Engl.
Calvoa rosularis Gilg ex Engl. requires periodic fertilization to maintain its growth. You can use a balanced, water-soluble fertilizer every month during the active growing season. Avoid over-fertilizing the plant because it can lead to burnt foliage or stunted growth. Make sure to follow the instructions on the label of the fertilizer you are using, to ensure you do not apply more than necessary.
Pruning for Calvoa rosularis Gilg ex Engl.
Calvoa rosularis Gilg ex Engl. does not require a specific pruning technique. However, pruning can help prevent legginess or sprawling growth. You can trim off dead or yellowing leaves to give the plant a cleaner appearance. You could also reshape the plant by trimming its growing tips and encourage healthier and fuller growth. You may prune the plant once or twice a year using sterile scissors or pruning shears.
Propagation of Calvoa rosularis Gilg ex Engl.
Calvoa rosularis Gilg ex Engl. can be propagated through various methods such as seed propagation, cutting propagation, and division propagation.
Seed propagation
Seeds are collected after the fruit has ripened and then dried under shade. The seeds can be sown in a seedbed or potting mixture and covered with a thin layer of soil. The seedbed or the potted seedlings can be placed in a warm, humid area with indirect sunlight. Germination occurs in 1-2 weeks, and the seedlings can be transplanted after they have grown 2-3 leaves.
Cutting propagation
Softwood cuttings of Calvoa rosularis Gilg ex Engl. can be taken from the parent plant and rooted in a potting mixture. The cuttings should be about 4-5 inches long with two or three nodes and should be taken in the early morning. The lower leaves should be removed, and the stems should be dipped in a rooting hormone before being planted in the potting mixture. The cuttings are then placed in a warm, humid area with indirect sunlight, and once rooted, they can be transplanted.
Division propagation
The plant can also be propagated through division, which is best done during the spring or early summer. The parent plant is carefully dug up and lifted from the soil. The plant is then divided into smaller clumps, making sure that each clump has roots attached. The smaller clumps are then immediately replanted in a suitable soil mixture, and kept in a warm, humid area with indirect sunlight until they have established roots and are ready to be transplanted.
Disease Management
The Calvoa rosularis Gilg ex Engl. plant is susceptible to different diseases such as bacterial leaf spot, root rot, and powdery mildew.
Bacterial leaf spot appears as water-soaked leaf lesions, which later turn brown and cause the leaves to fall. To prevent this, pruning of the infected area and proper sanitation on the affected plant is critical. The use of copper-based fungicides can help prevent the spread of the disease.
Root rot caused by fungi can cause stunted growth and yellowing of leaves. Lack of proper drainage, overwatering, and poor soil conditions are common causes of root rot. To manage this, the affected plants should be destroyed and the soil treated with fungicides.
Powdery mildew attacks the leaves and appears as a greyish-white layer on the leaves and stem. Fungi cause this disease. Spraying with neem oil or horticultural oils can serve as a preventive measure against powdery mildew.
Pest Management
The Calvoa rosularis Gilg ex Engl plant is susceptible to pests like spider mites, mealybugs, and aphids.
Spider mites cause yellowing of leaves and appear to be dots on the foliage of the plant. They are usually found on the underside of the leaves. To manage spider mites, regular washing of the plant is essential. Introducing predatory mites and spraying with insecticidal soaps can also help manage spider mites.
Mealybugs appear as cottony masses and can be located on the underside of the leaves. They suck sap from the plant, leading to stunted growth and discolored foliage. Insecticidal soaps or neem oil sprays can help manage mealybugs.
Aphids are tiny insects that suck sap from the plant, causing curled and distorted leaves. Regular monitoring and pruning of infected areas, as well as introducing beneficial insects such as ladybugs, can help control the infestation of aphids.
