Origin
Bulbophyllum purpureorhachis (De Wild.) Schltr. is native to West Africa, including the countries of Cameroon, Gabon, and Congo.
Common Names
The plant is commonly known as Purple-stemmed Bulbophyllum, in reference to the purple coloration of its stem. It is also known as De Wildeman's Bulbophyllum, after the Belgian botanist Émile Auguste Joseph De Wildeman who first described the plant in 1917.
Uses
Bulbophyllum purpureorhachis is primarily a decorative plant, appreciated for its small, colorful flowers and striking purple stem. It is commonly grown as an ornamental plant in tropical and subtropical regions around the world. Like many other species in the genus Bulbophyllum, this plant has limited practical uses beyond its decorative value.
General Appearance
Bulbophyllum purpureorhachis is an epiphytic orchid, growing on the trunks and branches of other trees. It has a short stem with elongated, narrow leaves that are typically arranged in a single row. The stem of the plant is a distinctive deep purple color, which is where it gets its common name. The inflorescence of the plant consists of several small, bright yellow or orange flowers that grow in clusters.
Light Requirements
Bulbophyllum purpureorhachis grow best in bright but indirect light. Avoid placing them in direct sunlight, as it can lead to leaf scorching. They thrive under fluorescent light or in a semi-shaded area with some dappled sunlight.
Temperature Requirements
This plant prefers a warm climate and requires a minimum temperature of 15°C (59°F) for growth. Optimal growth occurs in temperatures ranging between 20°C (68°F) and 25°C (77°F). Low temperatures can cause stunted growth, while too much heat and humidity can increase the risk of fungal infections.
Soil and Water Requirements
Bulbophyllum purpureorhachis should be planted in well-draining soil that holds moisture but doesn't retain excess water, as it can lead to root rot. A suitable potting mix for this plant should be a mix of peat moss, perlite or coarse sand, and bark. Water your plant sparingly, allowing the soil to dry out slightly before the next watering. Over-watering can cause the plant to rot.
Cultivation methods
Bulbophyllum purpureorhachis is an epiphytic orchid species that requires a well-draining medium such as fir bark, sphagnum moss, or perlite. It can be grown in hanging baskets or mounted on a slab of tree fern or cork. The plant prefers bright, filtered sunlight and high humidity, therefore it does well in a greenhouse or terrarium. The ideal temperature range for Bulbophyllum purpureorhachis is 65-75°F during the day and about 10 degrees cooler at night.
Watering needs
As with most orchids, Bulbophyllum purpureorhachis needs to be watered thoroughly but allowed to dry slightly between waterings. Overly wet conditions can cause root rot, so it is important not to let the plant sit in standing water for extended periods. Depending on the humidity levels in the growing environment, the plant may require watering every 5-7 days.
Fertilization
Bulbophyllum purpureorhachis benefits from regular fertilization during the growing season, which typically runs from spring through fall. Use a balanced, water-soluble fertilizer, diluted to half-strength, every 3-4 weeks. During the winter months, reduce fertilization to once a month or suspend it altogether to allow the plant to rest.
Pruning
Pruning is not typically necessary for Bulbophyllum purpureorhachis unless the plant has outgrown its container or needs to be divided. When repotting, remove any dead or damaged roots and trim off any old pseudobulbs that are soft or shriveled. If the plant has become too large, it can be divided into smaller sections with at least 3-4 pseudobulbs and replanted in separate containers.
Propagation Methods for Bulbophyllum purpureorhachis
Bulbophyllum purpureorhachis, commonly known as the Purple-ridged Bulbophyllum, is a terrestrial or epiphytic orchid species that belongs to the family Orchidaceae. This plant is native to Western Africa, including Sierra Leone, Ivory Coast, and Nigeria. Propagation of Bulbophyllum purpureorhachis can be done through three methods: division, stem cuttings, and seed sowing.
Propagation through Division
Division is the easiest way to propagate Bulbophyllum purpureorhachis. This method involves separating the parent plant into smaller sections that have at least two pseudobulbs each. During the division, it is important to ensure that each pseudobulb has roots attached to it. The newly divided sections should be replanted into separate pots using a potting mix that is well-aerated and free-draining. Water the newly divided sections with care and keep them in a warm and humid environment for several weeks until they are established.
Propagation through Stem Cuttings
Bulbophyllum purpureorhachis can also be propagated through stem cuttings. Take a healthy stem cutting that has at least two nodes, and make a clean cut using a sterile knife. Dip the cut end in rooting hormone, and plant it in a well-draining potting mixture that contains perlite, vermiculite, and peat moss in equal parts. Water the cutting well, and provide it with a warm, humid environment. Keep the soil lightly moist, and wait for new growth to emerge in a few weeks.
Propagation through Seed Sowing
The third method of propagating Bulbophyllum purpureorhachis is through seed sowing. Collect seeds from a mature and healthy plant, and sterilize them using hydrogen peroxide. Sow the seeds in a potting mix containing vermiculite, perlite, and sphagnum moss in equal parts. Cover the pot with a plastic cover, and keep it in a warm and humid environment. Once the seeds germinate, remove the cover, and continue to provide a humid environment. Gradually reduce the humidity level as the newly germinated plants mature.
Disease and Pest Management for Bulbophyllum Purpureorhachis
Bulbophyllum purpureorhachis is a beautiful and popular orchid that is native to the African rainforests. These plants are not only striking in appearance but also quite delicate. They are susceptible to various pests and diseases such as spider mites, scale, mealybugs, and bacterial or fungal infections.
Common Pests
Spider mites are one of the most common problems that plague Bulbophyllum purpureorhachis. You can identify spider mites by the tiny, red-colored spots on the leaves. They suck nutrients out of the plant, causing stunted growth and yellowing of leaves. Scale and mealybugs are other pests that feed on the plant sap and weaken the plant. You can identify scale by their brown or black shells, while mealybugs look like cottony masses on the plant.
Pest Management
One of the best pest management strategies is prevention. Regularly inspect your plant for any signs of pests and isolate infected plants from healthy ones. If you find any pests on the plant, immediately remove them using a cotton swab dipped in alcohol. You may also use insecticidal soaps or neem oil spray on the infected parts of the plant.
Common Diseases
Bacterial and fungal infections are common in Bulbophyllum purpureorhachis. Over-watering and high humidity levels can encourage the growth of bacteria or fungi. The leaves may turn yellow with brown spots or develop black rot.
Disease Management
Proper cultural practices can help prevent bacterial and fungal infections. Always use well-draining soil and avoid over-watering. Ensure there is enough air circulation around the plant to reduce humidity levels.
If the plant becomes infected, remove the diseased parts and cut off any rotten roots. Treat the remaining healthy parts with a fungicide or bactericide to prevent the spread of the disease.
By being vigilant and taking appropriate measures against diseases and pests, you can ensure the health and longevity of your beautiful Bulbophyllum purpureorhachis.
