Korean spice viburnum is a type of moderate sized shrubs that have clove-scented white flowers in spring, beautiful red foliage in fall, and red decorative berries in winter. The shrubs are great additions to cottage-style gardens and for those who prefer spicier scents to heavy floral scents. The Korean spice viburnum attracts songbirds and butterflies but can also attract less desirable guests: insects and pests.
What are some of the insects to watch for if you have a Korean spice viburnum?
Viburnum Leaf Beetles
Viburnum leaf beetles start as bumpy dark egg sacs on the underside of branches growing in the early spring. The larvae hatch in the late spring and early summer and start eating through the vascular system on the shrub's leaves. Affected leaves can start to take on a skeletal look as the larvae eat their way through the healthy tissue. Once the beetles become adults, the damage becomes larger and more notable with large holes appearing in affected leaves.
Early in the spring, call in a tree care service to thoroughly check the Korean spice viburnum for signs of leaf beetle eggs. The tree service can at that point manually remove the egg sac without causing any damage to the shrub's leaves.
If the larvae or adults have already started causing damage to the shrub, the tree care service will need to apply a pesticide and then manually remove any remaining beetles. The service will also need to watch that the adult beetles don't simply flee to other untreated shrubs or trees.
The Japanese beetle is a tiny, green- and copper-colored pest that can infest a Korean spice viburnum shrub. The behavior is similar to the leaf beetle in that Japanese beetle larvae eat through and skeletonize the shrub's leaves during the early spring growing season.
Japanese beetles are most treatable during the egg and early larvae stages since the beetles start off growing in the surrounding soil and grass rather than on the shrub. There's a commercially available tree disease that your tree service can purchase that will infect and kill the growing beetles without causing any damage to your shrubs.
Mealybugs are small, soft-bodied white insects with waxy filaments protruding from the bodies. The hatched larvae form thick, sticky masses that are easy to spot on the leaves of the shrub. The larvae will eat through healthy plant material including the leaves, flowers, and supporting branches. Feeding larvae can also emit a honeydew substance that can drip all over the shrub and leave the shrub susceptible to the tree disease black sooty mold and can attract an ant infestation.
The best way to get rid of mealybugs is to ask a tree care or pest control service to manually remove the pests. The removal can be done by hand and with a combination of plant-safe soap, heat, and water. Contact a business that handles tree services for more information.