Overview
Diporidium macrocalyx (Oliv.) Tiegh. is a tropical plant species commonly known as "Koraima" and is part of the Dipterocarpaceae family. It is a medium-sized tree native to the tropical rainforests of Southeast Asia, particularly in Indonesia and Malaysia, and is known for its valuable timber and medicinal properties.
Appearance
The Diporidium macrocalyx tree can grow up to 40 meters tall, with a trunk diameter of up to 1.5 meters. Its bark is grey and smooth, and its leaves are large, oblong-shaped, and glossy. It produces small white flowers that bloom in clusters, followed by elliptical fruit that can reach up to 4 cm in diameter. The fruit has a hard shell and contains a single seed that is surrounded by a fleshy aril.
Uses
The timber of Diporidium macrocalyx is highly valued in the construction industry due to its strength and durability, and is also used for furniture and boat building. Its roots and bark are traditionally used in medicine to treat various ailments such as fever, dysentery, and malaria. The aril surrounding the seed is edible and is used to make sauces and seasoning, and the seed itself has potential as a source of edible oil.
Additionally, the tree is important ecologically and contributes to the region's biodiversity by providing habitat and food for wildlife. Its seeds are dispersed by various animals, including elephants and primates, and the plant has a mutualistic relationship with some species of bees, which help pollinate the flowers.
Light Requirements
Diporidium macrocalyx is accustomed to thriving under bright light conditions, but it does not prefer to be in direct sunlight. It is well suited for shaded environments where it can receive a significant amount of diffused light. Placing the plant near a window that faces north can provide it with the perfect balance of brightness and shade.
Temperature Requirements
The ideal temperature range for Diporidium macrocalyx is between 16°C and 22°C. Although it can tolerate slightly cooler temperatures, the plant should not be exposed to frost or temperatures below 10°C. The optimum temperature for growth is around 20°C, with increased growth rates being observed at this temperature.
Soil Requirements
The majority of the Acanthaceae family prefers well-drained soils with a slightly acidic pH of around 6-7. Diporidium macrocalyx is no exception. It thrives in soils that are fertile and slightly rich, with organic matter mixed to enhance the soil structure. To promote good drainage, you can add sand or perlite to the soil mix. It is recommended to use a soil mix that contains a little bit of peat moss, compost, and vermiculite. This will ensure good drainage while also providing the plant with the necessary nutrients to grow.
Cultivation
Diporidium macrocalyx is a tropical plant that requires a warm and humid environment. It should be planted in well-draining soil with a pH range of 5.5-7.0. The plant can be propagated through seed or stem cuttings.
It is recommended to plant the Diporidium macrocalyx in a container that is at least 8-10 inches in diameter to provide ample space for the roots to grow. The container should be filled with a mixture of sand, peat moss, and perlite to ensure good drainage and aeration.
The plant should be placed in a location that receives bright, indirect sunlight for most of the day. It can also tolerate partial shade.
Watering Needs
Diporidium macrocalyx requires frequent watering to keep the soil consistently moist but not waterlogged. The soil should be checked regularly, and water should be added when the top inch feels dry to the touch.
The plant should be watered less frequently during the winter months when it goes into a dormant state. However, it should not be allowed to dry out completely.
Fertilization
Diporidium macrocalyx should be fertilized using a balanced, water-soluble fertilizer every two weeks during the growing season. The fertilizer should be diluted to half-strength to prevent overfertilization, which can damage the roots.
The plant should not be fertilized during the winter months when it is dormant.
Pruning
Dead or yellowing leaves and stems should be pruned away from the plant with a sharp, sterile pair of scissors to prevent the spread of disease.
It is also possible to shape the plant by removing the tips of the stems. This will encourage branching and create a fuller plant. Pruning can be done at any time of year, but it is typically best to do so in the early spring or summer when the plant is actively growing.
Propagation of Diporidium macrocalyx (Oliv.) Tiegh.
Diporidium macrocalyx (Oliv.) Tiegh., commonly known as the Madagascar croton, is a tropical plant that can be propagated by various methods, including seed propagation, cuttings propagation, and layering propagation.
Seed Propagation
Propagation of Diporidium macrocalyx (Oliv.) Tiegh. through seeds is possible, but it is a slow process and may take several weeks to months. The seeds should be collected from mature fruits that are fully ripe. They should be cleaned and sown in a well-draining potting mix. The seeds must be kept moist and warm until the germination occurs.
Cuttings Propagation
Propagation through stem cuttings is one of the easiest and most common methods for propagating Diporidium macrocalyx (Oliv.) Tiegh. The cuttings should be taken from the mature stems, preferably in the spring season. The cuttings should be dipped in rooting hormones before planting them in a well-draining potting mix. They must be kept in a warm and humid environment until the roots develop.
Layering Propagation
Propagation through layering is also possible in Diporidium macrocalyx (Oliv.) Tiegh. This method involves bending one of the mature branches towards the soil and covering it with a layer of soil. The branch should be kept in place with the help of pegs. The branch will develop roots after a few weeks, and it can be severed from the parent plant and transplanted to its permanent location.
Disease Management
Diporidium macrocalyx is generally a hardy plant but may be susceptible to certain diseases. The most common diseases that can affect this plant include:
- Fungal Leaf Spot: This disease is characterized by small round spots on the leaves. The spots may be yellow, brown or black, depending on the stage of the infection. To manage this disease, it is important to prune any affected leaves and dispose of them properly. Avoid overhead watering and ensure proper air circulation around the plant.
- Powdery Mildew: This fungal disease appears as a white, powdery substance on the upper surfaces of the leaves. To manage powdery mildew, avoid overcrowding the plants and provide good air circulation. Avoid overhead watering and treat the plant with a fungicide if needed.
- Root Rot: This disease is caused by a water mold and can cause wilting or yellowing of the leaves. To prevent root rot, ensure that the plant is not overwatered and that proper drainage is in place. If root rot is suspected, remove the plant from the soil and trim any infected roots before repotting in a well-draining soil mix.
Pest Management
Diporidium macrocalyx may also be susceptible to certain pests. Common pests that can affect this plant include:
- Aphids: These small insects can suck the sap from the plant and cause distortion of the leaves. To manage aphids, spray the plant with a strong jet of water to dislodge them or treat with an insecticidal soap.
- Spider Mites: These pests are tiny and can infest the underside of the leaves. Infested leaves may appear speckled or discolored. To manage spider mites, treat the plant with a miticide or insecticidal soap.
- Mealybugs: These pests are small and white and can cause wilting of the plant. To manage mealybugs, wipe the leaves with a cotton swab dipped in alcohol or treat the plant with an insecticidal soap.
Regularly inspecting the plant and maintaining a healthy growing environment can help to prevent the onset of diseases and infestations. Proper hygiene practices, such as cleaning tools and regularly removing fallen leaves, can also help to reduce the risk of disease spread.
