Overview of Viburnum prunifolium L. var. globosum Nash ex Schneid.
Viburnum prunifolium L. var. globosum Nash ex Schneid., commonly known as the blackhaw viburnum, is a deciduous shrub that belongs to the Caprifoliaceae family and is native to the eastern United States.
The plant's appearance
The blackhaw viburnum plant reaches a height of 12-15 feet and spreads to 8-10 feet. The shrub has a dense, rounded habit and a multistemmed growth habit. Its dark green, glossy leaves are oval or elliptical in shape, measuring about 2-4 inches long and 1-2 inches wide. In the fall season, the blackhaw viburnum’s foliage changes to shades of orange, red, and yellow. In the late spring season, the plant produces small white flowers that cluster together, making up the bloom. These flowers are followed by small blue-black fruits that are consumed by birds and other wildlife.
Common names
The Viburnum prunifolium L. var. globosum Nash ex Schneid. is commonly known as the blackhaw, southern blackhaw, wild raisin, and sweet haw.
Uses
The blackhaw viburnum plant is not only aesthetically pleasing but also has several practical uses. The fruits of the plant are edible and used to make jams, jellies, and wines. Native Americans and early settlers used the bark and roots of the plant for medicinal purposes, including treating cramps and menstrual problems. Today, the plant is still used in herbal remedies to treat certain health conditions. The plant is also used as an ornamental in landscaping due to its attractive appearance.
Light Requirements
Viburnum prunifolium L. var. globosum Nash ex Schneid., commonly known as the Blackhaw, prefers full sun to partial shade. However, excessive exposure to direct sunlight can be detrimental to the plant's growth and development. Therefore, it is recommended to provide at least 4-6 hours of direct sunlight per day, and the plant should be protected from intense midday sun.
Temperature Requirements
Blackhaw thrives in moderate temperature ranges. The ideal temperature for the plant’s growth is between 60°F-75°F. The plant is hardy in USDA zones 3-9, which indicates that it can tolerate a wide range of temperatures. However, it is important to note that extreme temperatures, specifically heavy frost and extended periods of intense heat, can be detrimental to the plant’s health.
Soil Requirements
Blackhaw prefers well-drained soils that are slightly acidic and rich in organic matter. The optimal pH range for the plant is 5.5-7.0. Soil that retains water for an extended period should be avoided as it can lead to root rot. Additionally, adding organic materials like leaf litter, compost, and aged manures to the soil will improve its fertility and help the plant to establish a robust root system.
Cultivation of Viburnum prunifolium L. var. globosum Nash ex Schneid.
Viburnum prunifolium L. var. globosum Nash ex Schneid. is a shrub that is commonly known as the blackhaw or southern blackhaw. This plant thrives in full sun to partial shade and typically grows to a height of 12 feet and a spread of 10 feet. When planting the shrub, ensure that the soil is well-draining, rich in organic matter, and has a pH between 5.5 to 6.5. Planting is best done in the fall or spring.
When planting, ensure the hole is at least two to three times the size of the root ball. Remove any damaged or diseased leaves, stems, or roots before planting. After planting, give the shrub a good watering to ensure that the roots make good contact with the soil.
Watering Needs
Viburnum prunifolium L. var. globosum Nash ex Schneid. requires adequate watering to establish, but once established, the shrub is relatively drought tolerant. Water the plant deeply at least once a week, providing 1 to 2 inches of water per week. Watering can be reduced during the winter months when the plant is dormant.
Fertilization
The Viburnum prunifolium L. var. globosum Nash ex Schneid. plant will benefit from a balanced slow-release fertilizer that is rich in phosphorus. Apply the fertilizer in early spring, just before new growth appears. Keep the fertilizer at least 6 inches away from the base of the plant and water the plant deeply after fertilizing.
Pruning
Pruning is typically not necessary for Viburnum prunifolium L. var. globosum Nash ex Schneid. shrubs unless you want to shape the plant or remove damaged or dead branches. If pruning is necessary, it's best to do it after the plant has finished flowering in the spring. To prune, remove up to one-third of the plant's branches, making cuts just above a healthy bud or branch junction. Avoid pruning during the winter months when the shrub is dormant.
Propagation of Viburnum prunifolium L. var. globosum Nash ex Schneid.
Viburnum prunifolium L. var. globosum Nash ex Schneid. can be propagated through various methods. The common methods of propagation include seed propagation, stem cuttings, and layering.
Seed Propagation
Seed propagation is the easiest and most common method for propagating Viburnum prunifolium L. var. globosum Nash ex Schneid. It can be done by collecting the berries from the plant when they are ripe. The seeds can be separated from the pulp and can be sown in a well-draining soil mixture. The soil should be kept moist and the seeds should be kept at a temperature of about 20°C to 25°C until germination occurs, which usually takes two to three weeks.
Stem Cuttings
Stem cuttings can also be used to propagate Viburnum prunifolium L. var. globosum Nash ex Schneid. Cuttings should be taken from the current season's growth during the spring or early summer months. The cuttings should be about 10 to 15 cm long with a few nodes. Remove the leaves from the lower part of the stem and plant it in a well-draining soil mixture. The soil should be kept moist and the cuttings should be kept at a temperature of about 20°C to 25°C until roots develop, which usually takes three to four weeks.
Layering
Layering is also a successful method of propagating Viburnum prunifolium L. var. globosum Nash ex Schneid. The layering process involves bending a low-growing branch of the plant down and with a sharp knife, make a shallow cut in the section of the stem that is touching the soil. Pin the wounded section down with a small stake or rock and cover the section of the stem with soil. The area should be kept moist and the roots should develop within a few months. Once the roots have developed, the new plant can be separated from the parent plant by cutting the stem from the parent plant.
Disease Management
Viburnum prunifolium var. globosum is generally resistant to diseases. However, it is still vulnerable to some fungal and bacterial diseases.
Fungal diseases that may affect the plant include powdery mildew, leaf spot, and Botrytis blight. To manage these diseases, it is recommended to prune the plant regularly to promote good air circulation and remove affected leaves and branches. Fungicides like copper-based sprays can also help in controlling these diseases.
Bacterial diseases like bacterial leaf spot and fire blight may also affect Viburnum prunifolium var. globosum. Pruning and removing infected leaves and branches are also helpful in managing these diseases. The use of copper-based bactericides may also be applied to control bacterial leaf spot.
Pest Management
Several pests may attack Viburnum prunifolium var. globosum. Here are some common pests and management methods:
Aphids: These insects suck plant sap, causing leaves to curl and yellow. To manage them, apply insecticidal soap or neem oil, or introduce natural predators like parasitic wasps and ladybugs.
Spider mites: They are tiny pests that can cause leaf yellowing and drying. Applying insecticidal soap and neem oil can help control spider mites. Pruning infested branches may also help prevent the spread of infestation.
Scale insects: These insects can cause yellowing and weaken the plant. Pruning and removing infested branches can help prevent infestation. Insecticidal soap and horticultural oil may also be applied to control scale insects.
Japanese beetles: Adult Japanese beetles feed on leaves and flower buds, causing skeletonized leaves and stunted growth. To control these pests, handpick the beetles and introduce natural predators like parasitic wasps. Applying insecticidal soap and horticultural oil may also help control Japanese beetles.
Regular monitoring, proper plant care, and preventive measures can effectively manage diseases and pests on Viburnum prunifolium var. globosum.
