Origin
Bothriocline argentea (O.Hoffm.) Wild & G.V.Pope var. ungurensis C.Jeffrey is a subspecies of Bothriocline argentea, a plant species native to southern Africa. It can be found in Angola, Namibia, and South Africa.
Common Names
This plant is commonly known as the Silver-leaf bush or Silwerblaarbossie in Afrikaans
Uses
The Bothriocline argentea var. ungurensis is used for ornamental purposes due to its attractive appearance; the leaves are covered in white, silky hairs which give it a silvery appearance, especially in bright sunlight. Its flowers are also quite beautiful, with yellow centers surrounded by white petals.
General Appearance
The Bothriocline argentea var. ungurensis is an evergreen shrub that can grow up to 2m tall. The leaves are long and narrow, measuring about 5cm in length and 1cm in width. The foliage is densely packed and the leaves are covered in white, silky hairs, giving it a silvery appearance. The flowers are quite striking with yellow centers surrounded by white petals, and is about 3 - 4 cm in diameter.
Typical Growth Conditions for Bothriocline Argentea Var. Ungurensis
Bothriocline argentea var. ungurensis is a perennial plant species that is commonly found in rocky areas and high elevation grasslands. To ensure proper growth and development of the plant, the following growth conditions should be provided:
Light
Bothriocline argentea var. ungurensis requires a lot of sunlight to grow and thrive. The plant prefers full exposure to the sun, and it is recommended that it receives at least six hours of direct sunlight per day. Lack of sunlight may cause the plant to grow weak and stunted.
Temperature
The plant can tolerate a wide range of temperatures but thrives in moderate temperatures. It can withstand high temperatures but not extreme heat. The ideal temperature range for Bothriocline argentea var. ungurensis to grow is between 15 °C and 25 °C. Extremely low temperatures may cause frost damage on the leaves and stems.
Soil
The plant grows in areas with well-drained soil that is nutrient-rich. Bothriocline argentea var. ungurensis prefers a slightly acidic soil with pH ranging from 5.0 to 6.5. It is recommended to use sandy loam soil that contains organic matter for best results. The plant does not thrive in heavy clay soils that retain water for extended periods.
Cultivation
Bothriocline argentea var. ungurensis is a hardy, drought-resistant plant that can tolerate various soil types, including clay, loam, and sandy soils. It thrives in full sun to partial shade and grows best in areas with mild temperatures.
The plant can be propagated from seeds or cuttings. If you're growing it from seed, sow seeds in well-draining soil and water moderately. For cuttings, ensure they're taken during the growing season and kept in a warm, dry place until they root.
When planting, ensure you space the plants appropriately to allow for proper air circulation. This will help prevent fungal diseases and other problems.
Watering Needs
Bothriocline argentea var. ungurensis is a water-wise plant that only requires watering when the soil is dry. Overwatering can lead to root rot and other moisture-related diseases. It's essential to water the plant deeply but infrequently, as this encourages deep root growth. During dry spells, you can water the plant every two to three weeks, depending on the soil and weather conditions.
Fertilization
Bothriocline argentea var. ungurensis is a low-maintenance plant that doesn't require much fertilization. If the plant is growing in poor soil, you can add a balanced fertilizer during the growing season. However, avoid fertilizing during the winter months, as this can encourage new growth that's susceptible to frost damage.
Pruning
Bothriocline argentea var. ungurensis doesn't require regular pruning, but you can trim it back to maintain its shape and promote bushier growth. The best time to prune the plant is during the late winter or early spring when the plant is dormant. Remove any dead, diseased, or damaged leaves or stems, as well as any crossing branches to encourage proper airflow.
Propagation of Bothriocline argentea var. ungurensis
Bothriocline argentea var. ungurensis can be propagated through various methods that are easy to carry out and require minimal expertise.
Propagation by Seeds
The plant can be propagated by seeds, which can be sown directly into the ground or started indoors. Seeds should be planted in well-draining soil under partially shaded areas and watered frequently. Germination typically occurs within four weeks, and seedlings should be transplanted once they have grown their second set of leaves.
Propagation by Cuttings
The plant can also be propagated by cuttings taken from the mother plant. Cuttings should be taken in the early spring from softwood stems, dipped in rooting hormone, and planted in a well-draining soil mix. The cutting should be covered, kept moist, and placed in a partially shaded area. Rooting typically occurs within six to eight weeks, and the new plant can be transplanted once it has developed a robust root system.
Propagation by Division
Bothriocline argentea var. ungurensis can also be propagated by division. This method involves separating the mother plant at the root system into two or more sections, each with their set of roots. Divisions should be performed in the early spring, and plants should be transplanted into well-draining soil under partially shaded areas. Water frequently until new growth appears.
Disease and Pest Management for Bothriocline argentea var. ungurensis
Bothriocline argentea var. ungurensis, commonly known as silvercrown or bushy aster, is a hardy plant species that is relatively resistant to diseases and pests. However, it's not entirely immune, and certain environmental conditions could lead to infections and infestations. Here are some common diseases and pests that could affect the plant, as well as ways to manage them.
Diseases
One of the most common diseases that affect Bothriocline argentea var. ungurensis is powdery mildew. This fungal disease forms white powdery patches on the leaves, stems, and flowers, leading to stunted growth and deformation of the plant. To manage powdery mildew, you can use a fungicidal spray or a homemade solution of water and baking soda. You can also prune the infected parts of the plant and ensure adequate air circulation and sunlight to prevent further spread.
Another disease that affects silvercrown is Leaf Spot, which manifests as round brown or black spots on the leaves and stems. This fungal infection can cause defoliation and weaken the plant. To avoid the spread of leaf spot, remove and destroy infected plant parts and avoid watering the plant from above. Treatment includes the use of a fungicidal spray or a copper-based fungicide.
Pests
One of the most common pests that attack Bothriocline argentea var. ungurensis is root-knot nematodes. These microscopic worms attack the roots, causing deformation, stunting, and wilting of the plant. Infected plants are more susceptible to other diseases and could eventually die. To prevent root-knot nematodes, rotate crops, avoid overwatering, and grow resistant cultivars. Also, avoid using infected soil or tools.
Another pest that could attack silvercrown is spider mites. These tiny arachnids form webs on the leaves, suck plant fluids, and cause chlorosis and curling of the leaves. To manage spider mites, spray the plant with water, insecticidal soap, or neem oil. You can also prune the infected parts and introduce predatory insects like lacewings or ladybugs to devour the mites.
Finally, aphids could also attack Bothriocline argentea var. ungurensis. These small insects pierce the plant tissues, suck sap, and secrete honeydew, attracting ants and forming sooty mold. To manage aphids, spray the plant with water, insecticidal soap, or neem oil. You can also introduce parasitic wasps or ladybugs to control the aphids.
