Introduction
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is a flowering plant that belongs to the family Asteraceae. It is commonly found in East Africa and is known for its unique appearance and medicinal properties.
Origin and Common Names
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is native to East Africa, specifically the countries of Kenya and Tanzania. It is commonly known as the "Mountain Bur Marigold" due to its high altitude habitat, as it is often found in areas above 2,000 meters.
The local people in Tanzania also refer to this plant as "Chamkoh kwa Miguu" which roughly translates to "sparkling feet," in reference to the plant's tiny shiny hooks on its seeds that often stick to clothing and shoes when brushed against.
Uses
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff has several medicinal uses in the East African region. The plant's leaves, stems, and roots are used to treat various ailments such as digestive problems, headaches, and malaria. The plant extract is also used as an insecticide and is effective in repelling pests and parasites such as ticks and fleas.
General Appearance
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is a herbaceous plant that grows up to 1 meter in height. The plant has a striking appearance, with bright yellow flowers that bloom from July to October. The flowers are arranged in clusters and have a distinct marigold-like appearance. The leaves are dark green and toothed, while the stem is hairy and sturdy.
The plant's seed heads are oval-shaped and have barbed hooks that stick to clothing and animal fur, aiding in seed dispersal. The plant prefers to grow in damp and rocky areas, including river banks, wet meadows, and marshes.
Light Requirements
Bidens kilimandscharica var. retrorsa requires full sunlight to thrive. It needs at least six hours of direct sunlight exposure each day for optimal growth. It can tolerate some shade, but too much shade can result in a leggy and weak plant.
Temperature Requirements
Bidens kilimandscharica var. retrorsa is a tropical plant that grows best in warm temperatures. It can tolerate temperature fluctuations but prefers to grow in temperatures between 20°C to 28°C (68°F to 82°F). Temperatures below 10°C (50°F) can damage or kill the plant.
Soil Requirements
Bidens kilimandscharica var. retrorsa prefers well-draining soils with a pH between 6.0 and 7.5. The soil should be fertile and rich in nutrients. It can grow in a wide range of soil types, such as sandy soil, loamy soil, or clay soil. However, the plant does not tolerate waterlogged soils. Therefore, it is essential to ensure that the soil is well-draining to avoid root rot.
Cultivation
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is native to East Africa and is commonly grown as a garden ornamental. It prefers a sunny or partially shaded location and well-draining soil. You can propagate the plant through seeds or stem cuttings, though seeds are easier to grow.
Plant the seeds or cuttings in the spring when the weather is warm. To grow from seed, plant them in a pot with a well-draining growing mix and place in a warm, sunny location. Keep the soil moist, and the seedlings should emerge within 7-21 days. Transplant the seedlings to their permanent location when they have grown to at least 2 inches tall. Alternatively, you can sow the seeds directly in the garden bed.
Watering Needs
The Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff plant needs regular watering to thrive. Water the plant deeply once per week during the growing season, and occasionally more during hot, dry weather. Stick to a regular watering schedule, as this plant does not like to dry out excessively. Avoid splashing water on the leaves and instead target the soil directly. Reduce watering during the winter months when the plant becomes dormant.
Fertilization
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff thrives when fed with a balanced fertilizer. Apply a slow-release, granular fertilizer to the soil in early spring before new growth appears. Repeat the application every two months during the growing season. Always follow the manufacturer's instructions regarding application rates. Alternatively, you can feed the plant with a liquid fertilizer every two weeks during the growing season.
Pruning
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff does not require extensive pruning. However, you can pinch back any leggy or overly long stems to promote bushier growth. Deadheading spent flowers will encourage the plant to produce more blooms. Cut back the entire plant to about a third of its height after flowering to encourage fresh growth. Prune damaged or diseased stems as soon as you notice them to prevent further issues.
Propagation Methods for Bidens kilimandscharica var. retrorsa
Bidens kilimandscharica var. retrorsa is a rare and beautiful plant that is native to high altitudes in Tanzania, specifically the Kilimanjaro and Meru mountains. It is commonly known as the "Shining Bidens" due to the shiny appearance of its leaves.
The plant can be propagated by both seed and vegetative methods, although seed propagation is the most common method used by growers.
Seed Propagation
To propagate Bidens kilimandscharica var. retrorsa from seed, you will need to collect mature seeds from a healthy plant. The seeds are generally small and should be collected when they turn brown and start to dry out. After collecting the seeds, they can be stored in an airtight container until you are ready to plant them.
Before planting, you will need to scarify the seeds by gently scraping the outer layer with sandpaper or a file. This will help to soften the seed coating and allow water to enter more easily, promoting germination. After scarification, soak the seeds in water for about 24 hours to help further soften the seed coat.
After soaking, plant the seeds in a well-draining soil mix, covering them with a thin layer of soil. Water the seeds lightly and place them in a warm, bright location. Keep the soil moist, but be careful not to overwater as this can cause the seeds to rot.
The seeds should germinate within 1-2 weeks, and once they have developed a few sets of true leaves, they can be transplanted into individual pots or containers.
Vegetative Propagation
Bidens kilimandscharica var. retrorsa can also be propagated by taking stem cuttings from a healthy plant during the growing season. To take cuttings, select a healthy stem and cut it just below a node. Remove the lower leaves from the stem, leaving only a few at the top.
Dip the cut end of the stem in rooting hormone and plant it in a well-draining soil mix. Water the cutting lightly and place it in a warm, bright location. Keep the soil moist and mist the cutting occasionally to help prevent it from drying out.
The cutting should root within a few weeks, and once it has developed roots, it can be transplanted into individual pots or containers.
Whether using seed or vegetative propagation methods, it is important to give Bidens kilimandscharica var. retrorsa plenty of light, water, and nutrients to help it grow strong and healthy.
Disease Management
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is relatively resistant to diseases, but it may be affected by some fungal and bacterial infections. Here are common diseases that may affect the plant:
- Leaf spots: Caused by fungi, leaf spots are circular or irregular spots on the leaves. Affected leaves may turn yellow and fall off. Fungicides can be effective in managing this disease.
- Powdery mildew: Powdery mildew is a fungal disease that affects the leaves of the plant, causing a white powdery substance on the leaves. Fungicides can also be effective in controlling this disease.
- Bacterial blight: This disease causes wilting, yellowing, and death of plant tissues. Copper-based fungicides can be used to control this disease.
Pest Management
Bidens kilimandscharica (O.Hoffm.) Sherff var. retrorsa Sherff is generally not heavily damaged by pests, but it can be affected by some pests. Here are common pests that may affect the plant:
- Aphids: These insects suck the sap from the plant and can cause deformation of the flowers. Insecticides can be effective in controlling aphids.
- Spider mites: These pests can cause yellowing and browning of the leaves. Insecticides and regular spraying of water can manage spider mites.
- Thrips: Thrips can cause the flowers and leaves of the plant to become distorted and may cause the flowers to fall off. Insecticides can be effective in controlling thrips.
