Korean spice viburnum is a beautiful and versatile shrub that requires little maintenance and thrives in many climates across the United States. The viburnum shrubs are available in dwarf sizes as accent plants or in larger sizes that can provide both ground cover and flowering hedges. The shrubs flower during the spring and summer, giving off a clove-like scent, and have leaves that turn a brilliant red in fall.
While the Korean spice viburnum is low maintenance from watering and fertilizing standpoints, you still need to periodically check the shrub for signs of diseases that can thwart the shrub's growth and beauty. Here are a couple of the tree diseases to watch for when you have Korean spice viburnum shrubs.
Powdery mildew is a fungal tree disease that is mostly a cosmetic concern, but since Korean spice viburnum is so beautiful, even a cosmetic problem can seem like a major setback. The mildew creates a thick, white powder or fuzz to form on the surface of leaves.
The mildew can also shed off the shrub onto the surrounding ground, sidewalk, or other plants. When the fuzz becomes severe on certain leaves, the affected leaves can stop receiving photosynthesis and will then die earlier than normal.
In the early stages of wilt, you can try clearing away the affected leaves and checking frequently to see if the disease remains and progresses. You can then call in a tree care service, which can apply a fungicide and trim the shrub to ensure the shrub is able to fight off the mildew once and for all.
Botrytis, also called gray mold, is another type of fungal disease that can strike your shrub. The disease can resemble powdery mildew at first since the associated fuzz starts out white but soon turns to a smoky gray tone that gives the disease its nickname.
Botrytis is more hazardous for the plant than powdery mildew, as the former will infect weak areas of the shrub, feed on the easy to eat tissue, and then grow strong enough to spread and consume healthy tissue. Flowers and leaves will both start to show signs of damage, browning, and will eventually die and fall from the tree.
You can minimize damage by calling in a tree service to carefully but fully remove any affected leaves and flowers both from the shrub and the surrounding ground. A fungicide can then be applied to help thwart off the disease.