Origin
Bulbophyllum sandersonii (Hook.f.) Rchb.f. subsp. sandersonii is a species of orchid native to Madagascar, a large island off the southeastern coast of Africa. It is commonly found in the eastern rainforests of the island, where it grows as an epiphyte, meaning it grows on other plants without taking any nourishment from them.
Common Names
The plant is commonly known as Sanderson's Bulbophyllum, named after the British orchid collector, Dr. John Sanderson, who discovered it in the 19th century. It is also sometimes referred to as the Satin-eared Bulbophyllum because of the shiny, purple, and fringed ears that grow from the center of its flower.
Uses
Bulbophyllum sandersonii (Hook.f.) Rchb.f. subsp. sandersonii is commonly grown as an ornamental plant in gardens and as a houseplant. Its unique appearance makes it a popular choice among orchid enthusiasts, and its fragrant flowers with a sweet vanilla-like scent are highly valued. The plant also has some medicinal properties, and its extracts are believed to have antifungal and antibacterial properties, which can be used to treat various skin diseases.
General Appearance
The Bulbophyllum sandersonii (Hook.f.) Rchb.f. subsp. sandersonii is a leafless epiphyte that grows up to 25 cm in height. It produces beautiful, large, and waxy flowers that are up to 7 cm in diameter. The flowers are usually dark purplish-brown in color with bright yellow margins, and the center of the flower is adorned with shiny, fringed purple ears that resemble butterfly wings. The plant blooms in the fall and winter months, and each inflorescence can have up to five flowers.
Light Requirements
The Bulbophyllum sandersonii thrives in bright, indirect light. Direct sunlight should be avoided as it can scorch and damage the leaves. It is best to place the plant near an east-facing window or a shaded west or south-facing window. If grown outdoors, it should be placed in a shaded area to protect it from prolonged exposure to sunlight.
Temperature Requirements
The Bulbophyllum sandersonii requires warm temperatures ranging from 60-80°F (15.5-26.5°C) during the day and 50-60°F (10-15.5°C) at night. The plant cannot tolerate extreme temperature fluctuations and should be kept away from drafts or areas with high temperature variations, such as near windows or doors.
Soil Requirements
The Bulbophyllum sandersonii grows well in well-draining soil mixes, such as a combination of bark, perlite, and peat moss. The soil pH should be slightly acidic, between 5.5-6.5. The plant should be repotted every two to three years, or when the soil has broken down and no longer provides adequate drainage.
Cultivation Methods
Bulbophyllum sandersonii (Hook.f.) Rchb.f. subsp. sandersonii is an epiphytic orchid native to Madagascar. It thrives in moderate light, high humidity, and warm temperatures. It can be cultivated in pots filled with a well-draining mix of bark, sphagnum moss, and perlite, mounted on slabs of bark, or hanging in baskets.
Watering Needs
This orchid requires frequent watering, but it is important not to keep the roots wet all the time. Watering must be done when the mix is almost dry and by submerging the pot in water until the mix is thoroughly moist. In dry environments, this species can also be sprayed frequently, especially during hot periods.
Fertilization
Bulbophyllum sandersonii (Hook.f.) Rchb.f. subsp. sandersonii must be fed regularly with a balanced fertilizer during its growing season. Fertilizing must be done every two weeks, and the amount per application must be low to avoid burning the roots. It is important to reduce fertilizing during the orchid's dormancy period.
Pruning
Pruning is not typically required for this orchid species. However, pruning is recommended to remove damaged or dead tissue, such as roots or leaves, to prevent the orchid from becoming diseased.
Propagation of Bulbophyllum sandersonii subsp. sandersonii
Bulbophyllum sandersonii subsp. sandersonii, popularly known as Sanderson’s Bulbophyllum, can be propagated through two popular methods: division and cloning through tissue culture.
Division
The easiest method of propagating Bulbophyllum sandersonii subsp. sandersonii is through division of an already established plant. This process should be undertaken during the plant's dormant stage, which is usually from the end of flowering to the beginning of the next growing season. Careful examination of the plant may reveal natural divisions, which can be cut away and potted individually. The divisions must have several pseudobulbs, a well-developed root system, and a healthy leaf.
It is important to ensure that the tools used for division are sterilized and that the plant is planted in a suitable substrate, such as a 50-50 mix of fir bark and sphagnum moss. The newly divided plants should be kept in a shaded area with high humidity levels until they are well-established, taking care to water them regularly.
Tissue culture cloning
Bulbophyllum sandersonii subsp. sandersonii can also be cloned through tissue culture, a laboratory-based technique that ensures genetic similarity and, therefore, the production of plants true to the parent plant. It involves taking a small sample of plant tissue and growing it in a sterile nutrient medium in a laboratory. Under strictly controlled conditions, the cells grow and multiply, and after several weeks, small plantlets are generated.
This propagation method is efficient, but it requires specialized equipment and expertise, making it expensive. The plantlets produced through tissue culture are fragile and must be hardened before planting in the soil.
Disease Management
Bulbophyllum sandersonii is generally a healthy plant that rarely succumbs to diseases. However, it can develop fungal or bacterial problems if grown in overly damp conditions or crowded space. The following are the most common diseases affecting this plant:
- Leaf spot: This disease is caused by fungal spores and usually manifests as brown or black spots on the leaves. To manage leaf spot, remove the infected leaves, improve air circulation, and avoid overhead watering.
- Crown rot: Crown rot is a fungal disease that affects the plant's stem base and causes the leaves to wilt. To manage crown rot, cut the infected plant parts and transplant the healthy ones to fresh soil.
- Botrytis: This is a gray fungal disease that can develop on the flowers and cause them to wilt. To manage Botrytis, remove the infected flowers and ensure the plant's humidity levels are low.
Pest Management
Bulbophyllum sandersonii can also be affected by common plant pests. Controlling the pests in the early stages of infestation helps protect the plant and prevent further damage to the plant's health and appearance. The following are the most common pests that affect this plant:
- Spider mites: These tiny insects drain the sap from the plant, causing it to weaken. To manage spider mites infestation, remove the infected parts of the plant and spray with insecticidal soap in a well-ventilated environment.
- Thrips: These tiny insects feed on the plant's flowers and leaves, causing them to become distorted and discolored. To manage thrips infestation, remove the infected parts of the plant and spray with insecticidal soap in a well-ventilated environment.
- Scale insects: These insects move slowly and feed on plant sap, causing the leaves to turn yellow or lose their shine. To manage scale insects, remove the pests manually from the plant leaves using a cotton swab dipped in rubbing alcohol.
