Origin
Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi, commonly known as Japanese buckthorn, is a deciduous shrub native to Japan, Korea, and Siberia. It belongs to the Rhamnaceae family, which includes about 800 species of shrubs and trees.
Common names
In addition to Japanese buckthorn, Rhamnus davurica ssp. nipponica is also commonly known as Korean buckthorn, East Asian buckthorn, and Oriental buckthorn.
Uses
Japanese buckthorn has several medicinal uses, particularly in traditional Chinese and Korean medicine. Its bark contains anthraquinones, which have laxative properties and are commonly used to treat constipation. The bark, leaves, and fruits of the plant can be used to treat other ailments such as edema, abdominal pain, and eczema. The fruits of the plant are also used to make a yellow dye.
Japanese buckthorn is also used in landscaping, particularly as a hedge or border plant. The plant's dense growth habit and prickly branches make it an effective barrier plant, while its attractive foliage and showy fruit make it a popular ornamental plant.
General appearance
Japanese buckthorn is a large, multi-stemmed shrub that can reach heights of up to 16 feet (5 meters). It has a dense growth habit and dark green leaves that turn yellow in the fall. The plant produces small, inconspicuous flowers in the spring, which are followed by small, round fruits that start out green and ripen to a deep red color. The fruits grow in clusters and persist on the plant through the winter.
The branches of Japanese buckthorn are covered in sharp, thorn-like protrusions, which can make it difficult to handle without gloves. The plant's roots are shallow and fibrous, which allows it to grow in a wide variety of soils.
Light Requirements
The Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi prefers to grow in full sun to partial shade. It can tolerate moderate shade but will produce fewer flowers and fruits. Exposure to direct sunlight stimulates the plant's growth and enhances its overall health.
Temperature Requirements
The Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi can adapt to a wide range of temperatures. However, it favors the moderate climate and does not prefer extreme temperature fluctuations. It can withstand sub-zero temperatures during winter dormancy, but the young shoots and leaves can be damaged by frost. The ideal temperature range for this plant is between 16 to 28°C (60 to 82°F).
Soil Requirements
The Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi can thrive in a variety of soil types, including sandy, loamy, or clay soils. However, it prefers a well-draining, fertile soil that is rich in organic matter. The pH range for the soil should be between 5.5 to 7.5, which is slightly acidic to neutral. It can tolerate slightly alkaline soil as well.
The plant does not like to grow in water-logged or poorly drained soil, which can cause root rot and other fungal diseases. Therefore, ensure that the soil is well-draining. Adding organic matter to the soil can improve the drainage and provide a steady supply of nutrients to the plant.
Cultivation
Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi, also known as Japanese buckthorn, can be grown in USDA plant hardiness zones 6 to 9. It prefers full sun to partial shade and well-drained soil. It can tolerate a variety of soil types, including sandy, loamy, and clay, but acidic soil with a pH range of 5.0 to 6.5 is ideal. This plant is also drought tolerant once established and can withstand occasional flooding.
Watering Needs
While Japanese buckthorn is drought tolerant, it requires regular watering during its early growth stages. During the first growing season, water your plant once a week. Once established, you can reduce watering frequency to once every two weeks. Providing about 1 inch of water per week through rainfall or manual irrigation is sufficient. However, ensure you avoid overwatering, as this can lead to root rot and plant decline.
Fertilization
For optimum growth and flowering, Japanese buckthorn requires proper fertilization. Apply a balanced fertilizer once a year in the early spring to provide sufficient nutrients for the growing season. Use a slow-release fertilizer to avoid over-fertilizing and damaging the plant. Additionally, organic mulch can be used to feed the plant regularly and help retain soil moisture.
Pruning
Japanese buckthorn requires minimal pruning, but shaping and trimming can be done during the plant's early years to establish a framework. Prune the plant in early spring before new growth emerges. Remove damaged, diseased, and dead branches using sharp and clean pruning tools. You can also prune the shrub to maintain the desired size or shape. Remember never to remove more than one-third of the shrub's overall size during pruning to avoid shocking the plant.
Propagation of Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi
Rhamnus davurica Pallas ssp. nipponica (Makino) Kartesz & Gandhi, commonly known as Japanese buckthorn, is a perennial plant that belongs to the family Rhamnaceae. It is a tough, low-maintenance plant that can be propagated through various methods.
Seed Propagation
One of the most preferred methods of propagation for Rhamnus davurica Pallas ssp. nipponica is through seeds. The seeds need to be harvested from the plant when they are fully mature and can be sown directly into the soil. However, before sowing, the seeds must be scarified and stratified. Scarification can be done by rubbing the seeds with sandpaper or soaking them in warm water for few hours. After scarification, the seeds should be stored in a moist, cool place for about two to three months. Once the seeds have been stratified and the temperature is right, they can be sown into the soil where they will germinate in a few days.
Cuttings Propagation
Another propagation method for Rhamnus davurica Pallas ssp. nipponica is through semi-hardwood cuttings. Cuttings should be taken from the plant when the wood is semi-hard, usually in the late summer season. The cuttings should be dipped in rooting hormone and placed in moist potting soil. The cuttings should be kept in a warm, humid area for about four to six weeks, and new roots should begin to appear. When the roots have developed, the cuttings can be transplanted into bigger pots or directly into the garden.
Division Propagation
Division is another propagation method for Rhamnus davurica Pallas ssp. nipponica, which involves dividing mature plants into smaller sections and re-planting them. This method is best done in the early spring season when new growth begins to appear. It is important to ensure that the division has a good portion of roots attached, which will have a higher chance of survival. The divided sections can be replanted immediately in pots or directly into the garden.
Disease Management
One of the most common diseases that affect Rhamnus davurica Pallas ssp. nipponica is powdery mildew. The fungus appears as a white powdery layer on the leaves, stems, and flowers of the plant. To manage this disease, one can use fungicide sprays or neem oil. It is important to regularly check the plant for signs of powdery mildew and remove any infected leaves or branches immediately to prevent the spread of the disease.
Another common disease that affects this plant is leaf spot. It appears as small black or brown spots on the leaves. To manage this disease, it is important to remove infected leaves, sterilize pruning tools, and use fungicide sprays.
Pest Management
One of the most common pests that affect Rhamnus davurica Pallas ssp. nipponica is scale insects. These insects appear as small bumps on the stems and leaves of the plant. To manage this pest, it is important to use horticultural oil or insecticidal soap sprays. It is also important to regularly inspect the plant for signs of scale insects and remove any infected stems or branches immediately to prevent the spread of the pest.
Another common pest that affects this plant is spider mites. These pests can cause leaves to turn yellow and fall off the plant. To manage this pest, one can use insecticidal soap sprays or neem oil. It is also important to regularly inspect the plant for signs of spider mites and remove any infected leaves or branches immediately to prevent the spread of the pest.
In conclusion, Rhamnus davurica Pallas ssp. nipponica is susceptible to various diseases and pests, and it is important to regularly inspect the plant for signs of infestation. Early detection and management of diseases and pests can help prevent the spread of the infestation and ensure the health and vitality of the plant.
