Viburnum beetles get their name from their habit of feeding and breeding on the leaves of the viburnum plant. Usually featuring lush clusters of white flowers, viburnum shrubs often work well as privacy screens around a yard or as focal plants in a landscape. These vibrant-looking plants can quickly wither and die from attacks by viburnum beetles. Fortunately, controlling these pests is usually a matter of choosing resilient viburnum varieties, proper pruning, and encouraging beneficial insect reproduction.
If you don’t already have a viburnum shrub, controlling viburnum beetles could involve little more than choosing a resilient shrub species. Dawn, Koreanspice, leatherleaf, and tea viburnum shrubs all have tough, hard leaves that are difficult for viburnum beetles to eat. They’re also usually very hardy and may be able to take a lot of abuse. This gives you more time to correct any infestations that do happen without worrying too much about irreparable damage.
Gardeners with any variety of viburnum shrub can control viburnum beetles by pruning. These little, copper-colored insects typically lay their eggs in mid-October and near the beginning of April. During these months, look for oily black residue on your viburnum leaves. These are viburnum beetle eggs. You may simply snip away these infected branches and discard them far away from your garden. Do not try to compost the infected leaves as the insects may be able to mature in the compost and cause an even worse infection.
People with aphid problems may already know about the wonders of ladybugs, but those that don’t should encourage them to breed in most gardens. You can mail-order ladybug eggs, larvae, and adults from many organic garden companies online. Some nurseries even sell them. Ladybug larvae and adults will typically feed on viburnum beetle larvae and adults, helping to combat the problem. Lacewing flies and soldier bugs will usually do the same thing.
When you encourage predatory insects to breed in your garden, they generally fight the viburnum beetles at every level. The larvae of each of these beneficial bugs will consume viburnum beetle larvae, and the predatory adults will consume the pestilent adults. Most beneficial insect packages come with care instructions, but those ordering adults usually need do little more than open the box in the garden. Placing the box under the infested shrub should help the friendly insects find the pesky beetles relatively quickly.
Those that note a viburnum beetle infestation after the larvae have hatched and matured may want to use pesticides to help kill off most of the population before adding beneficial insects. Most pesticides formulated for fruits and vegetables or made to kill greenflies should do the trick. Beneficial insects should not be introduced to shrubs treated with pesticides. If you want to use predatory insects, wait at least six months before introducing them to any area in which pesticides were used.
