Hibiscus plants can thrive indoors or outdoors, but their beautiful flowers and lush foliage guarantee that no matter where they are planted, they will present an irresistible temptation to your local bug population. Fortunately, there are a variety of ways to get rid of bugs on hibiscus plants, and since the hibiscus itself is fairly hardy, you will usually find that temporary defoliation is the most severe reaction to bug treatments.
Bugs can invade nearly any part of the hibiscus. They may lay eggs in the flowers or suck the sap right out of the plant. The bugs tend to live out at least one portion of their life cycle on the plant, then leave eggs so that the next generation can also enjoy your beautiful potted flower.
If your hibiscus is losing flowers, has yellowing leaves, has white speckles on the bark, flowers or leaves or has veined, brown marks on the leaves, you likely have bugs. In many cases, you will see the bugs themselves hiding under the leaves and in new growth. Left untreated, bugs on hibiscus can spread plant diseases and ultimately are likely to kill the plant.
Hibiscus bugs come in a variety of shapes and sizes. Spider mites are hard to see without a magnifying glass, but they make tiny webs on the plant. Thrips are narrow and dark-colored, while whiteflies, aphids and mealybugs appear to be white, brown or green dots on the plants. Ants also love hibiscus, and will crawl all over the plant.
If your plant is living indoors, an insecticidal soap will often do the trick. Use 1 tbsp. per gallon of pure water, and mist the plant with the soap solution. You can also cut off new growth to within about 4 inches of the main stem, which will certainly disfigure your plant temporarily, but will remove the hiding places most bugs on hibiscus plants prefer. Finally, if temperatures are below freezing, place your plant outside for about 20 minutes before bringing it back indoors. It will lose its leaves, but in most cases you will kill the bugs. However, you may not kill the eggs.
Use chemical pesticides on your hibiscus without fear of harming the plant. However, these pesticides tend to be harmful to the environment, pets and potentially humans. If your hibiscus is planted in the soil of a garden, you will be exposing your entire yard if you use chemical pesticides.