Bugs On Hibiscus and How To Identify & Control Common Pests

How To Identify And Control Unwanted Bugs On Hibiscus Plants

Most would agree that finding pests on hibiscus plants can be an immediate cause for concern. Though many common garden insects are considered beneficial, some species can quickly decrease the ornamental value of plants and may even harm or kill them. Learning to properly identify these troublesome pests will help you protect and treat your hibiscus beds before infestations become severe.

Common Hibiscus Pests

Aphids

The term “aphid” is commonly used to describe varying species of small, sap-sucking insects. Hibiscus plants in the home landscape are susceptible to damage caused by these pests, specifically, the cotton-melon aphid. As they are quite small, close inspection of the plant’s leaves and stems may be required. Common signs of aphid damage include stunted growth and the yellowing of the plant’s foliage.

Mites

Due to their size, spider mites are difficult to identify. However, gardeners often note a whitish “webbing” on the underside of the plant’s leaves as an indication that they are likely present. Large numbers of mites will cause yellowing foliage and premature dieback. Most populations can be removed from the plants with a simple blast of water.

Beetles

Japanese beetles are known for their ability to quickly destroy plant foliage. These large, iridescent beetles are easy to identify, feeding throughout the day, in plain sight. Though infestations of Japanese beetles seldom lead to the loss of hibiscus plants, their presence will decrease the plant’s overall health and ornamental appeal. Seasonal beetles can be hand-picked from plants or treated with insecticidal soaps.

Ants

Ants are commonly observed on hibiscus flowers because of their sweet nectar. Considered to be a good food source to ants, the insect will not cause damage to the plant or its flowers. Should the hibiscus show signs of stress, the presence of ants may indicate trouble with aphids, as they are attracted to the “honeydew” produced by the pests as they feed.

Sawflies

Hibiscus sawflies are known for their ability to quickly defoliate plants, leaving an unattractive lace-like appearance. After long periods of feeding, sawfly caterpillars will use hibiscus as a host plant for their cocoon. Sawfly caterpillars can be removed by hand-picking or the use of insecticidal soaps.

Whiteflies

Whiteflies are yet another small garden pest. Infestations first become noticeable when large numbers of nymphs cover both the top and underside of plant leaves. Though whiteflies can be treated with insecticides, experienced growers often suggest removing and destroying infected plants or foliage.

Mealybugs

Though most common indoors, mealybugs may also feed on plants in flower beds. These pests suck sap from the plant, causing damage to leaves and stems. Over time, injured hibiscus foliage will yellow and begin to turn black. Severe instances of mealybugs may be difficult to control, as their unique wax-like body makes them more resilient to insecticidal soaps.

Thrips

Thrips are a common source of damage to hibiscus foliage. Though small numbers of thrips are unlikely to cause notable injury to plants, large infestations may contribute to a diminished appearance, yellowing of leaves, and stunted growth. Hibiscus thrips may also cause flowers to become discolored or drop from the plant prematurely.

Scale

Various types of scale are considered to be extremely harmful to hibiscus plants. Rounded pests attach to stems and are covered in a protective waxy layer. Severe instances of scale are likely to lead to premature leaf drop, stem die-back, and the loss of plants. Most growers report success controlling scale through the use of neem oil or insecticidal soaps.

Other Pests on Hibiscus Plants

Twig pruner larvae, or borers, are also quite common in hibiscus plants. These pests burrow into the stems of plants and feed until they emerge much later in the season. Hibiscus plant bugs (Niesthrea louisianica) may also be an issue. However, damage caused by these insects is generally isolated to the plant’s seed and seed pods.

Hibiscus Pest Control

Biological Control Methods

When it comes to hibiscus, beneficial insects can play a major role in the biological control of pests. Many beneficial species feed on and actively help to control nuisance pests. Diversity among garden beds will help attract these “good bugs,” as well as serve as an invaluable resource to pollinators.

Cultural Control Methods

Bugs on hibiscus can also be controlled with the use of cultural methods. In most instances, this refers to the removal of pests by hand-picking. Other cultural controls include the management and removal of decaying plant matter and the use of proper garden sanitation techniques.

Chemical Control Methods

Chemical controls for the home garden vary greatly in terms of purpose and strength. Though effective, these products should always be used with care. Before use, gardeners should familiarize themselves well with each manufacturer’s label for safety, paying close attention to timing and application. Many chemical controls will also harm visiting pollinators and beneficial insects present within the ecosystem.

Note: Any recommendations pertaining to the use of chemicals are for informational purposes only. Chemical control should only be used as a last resort, as organic approaches are safer and more environmentally friendly.