Overview
Rhus discolor is a shrub or tree that belongs to the Anacardiaceae family. It is commonly found in Africa, particularly in Namibia, Botswana, and South Africa. The plant is also known as the blue-leaved currant, karree, and kareeboom.
Description
The Rhus discolor shrub or tree can grow up to 5 meters tall, with a distinct multi-stemmed and round-shaped crown. The bark is smooth and brownish-grey in color, with some noticeable vertical cracks. The leaves are deciduous, oval to round in shape, and have a blue-grey tint to them. The fruit produced by Rhus discolor is a small, round drupe that changes from green to reddish-black when it is ripe.
Uses
The Rhus discolor has several traditional medicinal uses for both humans and animals. The root bark, for instance, is used as an emetic, while the leaf infusion is used to treat skin rashes and sore throats. The plant is also a source of tannins, used for tanning leather. Additionally, the Rhus discolor tree produces a valuable hardwood used for furniture and tool handles.
Furthermore, the Rhus discolor is a popular ornamental plant in residential gardens and public spaces due to its attractive foliage. The tree requires little maintenance and is resistant to pests and diseases. Its attractive leaves are also used in floral arrangements.
Growth Conditions for Rhus discolor E.Mey. ex Sond.
Light: Rhus discolor thrives in full sunlight but can also tolerate partial shade. It is best to plant it in an area that receives at least 6 hours of direct sunlight per day.
Temperature: Rhus discolor is a drought-tolerant plant that can survive in a wide range of temperatures. However, it prefers warm temperatures between 65-85°F (18-29°C) during the day and cooler temperatures between 50-70°F (10-21°C) during the night.
Soil: Rhus discolor prefers well-draining soils with a neutral to slightly acidic pH range of 6.0-7.5. It can tolerate a range of soil types, including sandy, loamy, or clay soils. However, it does not do well in soils that are constantly wet or poorly drained.
Fertilizer: It is not necessary to fertilize Rhus discolor, but a light application of balanced fertilizer in the early spring can help promote growth. Avoid using high-nitrogen fertilizers, as they can promote leaf growth at the expense of flower production.
Water: Rhus discolor is drought-tolerant and does not require frequent watering once established. Water the plant deeply once a week during dry spells, and avoid overwatering as it can lead to root rot.
Pruning: Rhus discolor does not require extensive pruning, but occasional pruning can help maintain its shape and promote new growth. Prune in the late winter or early spring before new growth appears.
Cultivation Methods for Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond. is a shrub that can grow up to 10 feet tall and 8 feet wide. It can grow in a wide range of soil types, including sandy, loamy, and clay soils, but it prefers well-draining soils with a pH range of 5.0-7.5. It is a cold-hardy plant that can survive in USDA hardiness zones 7-10.
If planting Rhus discolor E.Mey. ex Sond. from seeds, it needs to be cold stratified before planting in the ground or in containers. Seeds can be stored in the refrigerator for 60-90 days before planting. Cuttings can also be used to propagate the plant.
Watering Needs for Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond. requires regular watering during the first growing season to establish a strong root system. Afterward, it can survive on rainfall alone, but it benefits from occasional watering during periods of drought. Overwatering can be detrimental to the plant and cause root rot.
Fertilization for Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond. is a low-maintenance plant and does not require regular fertilization. However, a balanced fertilizer can be applied in the spring to promote growth and blooming. Alternatively, compost or well-rotted manure can be added to the soil as a natural fertilizer.
Pruning Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond. is a shrub that benefits from regular pruning to maintain a compact shape and promote blooming. Pruning should be done in late winter or early spring before new growth appears. Dead, damaged, or diseased branches should be removed. Additionally, any branches that cross or rub against one another should be removed to prevent further damage.
Propagation of Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond., commonly known as the African sumac or the karee, can be propagated through different methods such as seed propagation, cutting propagation, and layering propagation. Each method has its own advantages and disadvantages, and the choice of method will depend on the grower's preference and resources.
Seed propagation
Seed propagation is a popular method for propagating Rhus discolor. The seeds should be collected from mature fruits and sown in well-draining soil. The seeds should be placed in a warm and bright location, and watered regularly to maintain soil moisture. The seedlings will emerge in a few weeks and can be transplanted to individual pots once they have developed a good root system. Seed propagation is a cost-effective method, but it takes longer to produce a mature plant compared to other methods.
Cutting propagation
Cutting propagation involves taking cuttings from a mature Rhus discolor plant and rooting them in a growing medium such as sand or peat moss. The cuttings should be taken during the active growing season, and the lowest leaves should be removed to expose the stem. The cuttings should be dipped in rooting hormone and inserted into the growing medium. They should be kept in a warm and bright location and watered regularly to maintain soil moisture. Cutting propagation is a quicker method than seed propagation, and it produces plants that are genetically identical to the parent plant.
Layering propagation
Layering propagation is a method where a branch of an adult Rhus discolor plant is bent towards the ground and covered with soil or a growing medium. The branch should be wounded where it touches the soil to encourage root development. The branch should be kept moist, and roots will eventually develop. Once the roots have developed, the branch can be separated from the parent plant and transplanted to a new location. Layering propagation is a reliable method, but it takes longer than cutting propagation.
Disease and Pest Management for Rhus discolor E.Mey. ex Sond.
Rhus discolor E.Mey. ex Sond. is a deciduous shrub that is native to southern Africa. This plant is relatively hardy and can tolerate a range of growing conditions. However, it is still prone to certain diseases and pests that can impact its growth and overall health. Below are some common diseases and pests of Rhus discolor E.Mey. ex Sond. and ways you can manage them.
Diseases
Anthracnose: This is a fungal disease that can cause leaf spots, stem cankers, and twig blight. To prevent anthracnose, avoid overcrowding plants and improve air circulation around the shrub. Remove infected plant debris immediately, and treat with a fungicide if necessary.
Powdery mildew: This is a fungal disease that causes a white, powdery coating on the leaves and stems. To prevent powdery mildew, water the plant at the base, and avoid overhead watering. Provide proper spacing between plants to allow for good air circulation. Treat with a fungicide if necessary.
Crown rot: This is a fungal disease that causes the plant to wilt and ultimately die. To prevent crown rot, avoid overwatering the plant and plant it in well-draining soil. Fungicides can be used to treat the disease, but prevention is the best approach.
Pests
Aphids: These tiny insects suck the sap out of leaves and stems, causing the plant to become weak and stunted. To get rid of aphids, blast the plant with a strong jet of water, or treat with insecticidal soap or oil.
Spider mites: These pests are so tiny they are often not visible to the naked eye. They feed on the leaves, causing yellowing and a stippled appearance. Spider mites prefer dry, dusty conditions, so regularly misting the plant can help prevent infestations. Treat infestations with insecticidal soap or oil.
Caterpillars: These pests can cause defoliation and weaken the plant. Handpicking caterpillars off the plant is an effective way to manage them. Bacillus thuringiensis (Bt) is a biological control that can be used to treat caterpillar infestations.
With proper care and attention, Rhus discolor E.Mey. ex Sond. can remain healthy and free of diseases and pests. Regularly inspect the plant for any signs of infestations or disease, and take action as needed to keep it in optimal condition.
