Viburnum macrocephalum is a species of flowering plant in the family Adoxaceae. It is native to China and Vietnam. The plant is known for its large, showy flowers. The flowers are white or pink, and they are borne in large clusters. The plant grows to a height of 2-3 m.
Related plant:
Viburnum Opulus Compactum
Related plant:
Viburnum Carlesii Aurora
About soil condition, Viburnum macrocephalum prefers a moist, humus-rich, well-drained soil, but it is quite tolerant of less than ideal conditions. It will grow in sun or shade, but it blooms best in full sun.
Not too different with other viburnums, the macrocephalum does best in full sun, but can tolerate some shade. An ideal spot for this shrub is one that gets sun for most of the day, but has some relief from the hot afternoon sun. It's also important to choose a spot with well-drained soil, as the macrocephalum is sensitive to wet conditions.
The temperature condition that is most favorable for the growth of viburnum macrocephalum is between 20 and 25 degrees Celsius. This plant is not very tolerant of extreme temperatures and can be damaged by temperatures that are either too high or too low.
Ideal humidity condition for this plant is 50% - 60%. If the plant is put in an environment with lower or higher humidity, the plant may experience some negative effects. For example, lower humidity can cause the leaves to dry out and drop off, while higher humidity can cause the plant to develop mold or mildew.
For the fertilizer, usually the plant will need a 10-10-10 or 20-20-20 mix. However, for the root, it is recommended that you use a 1-2-1 mix. This will ensure that the plant gets the nutrients it needs for a healthy root system.
Pruning viburnum macrocephalum is best done in late winter or early spring, before new growth begins. This shrub can be pruned quite severely, as it is very forgiving. Just be sure to take off no more than 1/3 of the shrub's overall height.
Propagation of Viburnum macrocephalum is typically done through softwood cuttings taken from new growth in late spring or early summer. The cuttings should be 4-6 inches long and taken from the tips of the stems. They should be placed in a moist, well-drained media and kept at a temperature of 68-72 degrees Fahrenheit. Cuttings should be taken from healthy plants that are free of pests and diseases.
Usually, the plant growth rate is between 10 and 15 feet (3 to 4.6 m) per year. However, some plants have been found to grow up to 24 feet (7.3 m) in a year. This fast growth rate is attributable to the plant's rapid reproductive cycle.
Common problems for this kind of plant are powdery mildew, rust, and leaf spot. Powdery mildew is a white, powdery fungus that can cover the leaves and stems of the plant. Rust is a yellow, orange, or red fungus that can cause the leaves to fall off. Leaf spot is a dark brown or black fungus that can cause the leaves to turn yellow and fall off.
Source:
Viburnum macrocephalum - UDBG
Viburnum macrocephalum (sterile) - UDBG Online Store - udel.edu
Viburnum - UC Master Gardener Program of Sonoma County