Small Black Bugs on a Hibiscus Plant

Identifying hibiscus pests is the first step toward eliminating them. Once you know what the insects are and how to get rid of them, your flowers will again have the opportunity to thrive. The bugs that invade hibiscus flowers usually cause more issues down the line if they are not taken care of right away, since many hibiscus pests not only damage the leaves and flowers, but also spread bacteria and disease to the plant.

Aphids

Forty generations of aphids may reproduce in one summer.

Perhaps the most common hibiscus insect is the aphid. Aphids are small black, green or white bugs that invade the bud and flower of the plant. They can be seen at the top of stems, near and on the flowers. They leave a sticky substance called "honeydew" on the leaves. Aphids reproduce at an alarming rate, so when the pests are first seen, the hibiscus should be treated as soon as possible. Natural predators include lacewings and ladybugs, but to completely rid your flowers of these tiny predators, you may need to use a systemic chemical containing imidacloprid.

Ants

Ants are proficient bug farmers.

Besides enjoying the hibiscus flower's nectar, ants love the sweet honeydew created by aphids and other sap-sucking insects. They carry pests and their eggs onto hibiscus leaves, farming and protecting them from other insects. Perhaps the best way to get rid of the ants is to first eliminate the insects they are farming. This may take weeks of careful observation and chemical use, but will control more than one pest problem. Another way to get rid of the ants is to use a bait that will be carried back to the nest. This will eliminate the queen and her colony.

Fungus Gnats

For healthy indoor hibiscus, buy new soil before potting.

If you've grown a hibiscus indoors, you may have seen common flying pests like fungus gnats. These insects look and fly like tiny mosquitoes. Fungus gnat larvae feed off fungus, which is common in potted plants. They then continue to feed off the plant's roots. Not only do they harm the root system, but these gnats also spread fungus, which is harmful to hibiscus. To get rid of fungus gnats, treat the larvae as well as the adults. You may need two separate insecticides to do this.

Shoreflies

Shoreflies will not damage the plant or the flower.

Unlike fungus gnats, shoreflies do not harm hibiscus plants, but they are a nuisance. These flying insects look and fly like miniature houseflies. They feed off of algae, which commonly grows on top of the soil of potted plants. To get rid of shoreflies, treat them with an insecticide for adult fungus gnats, and remove obvious algae growth from your hibiscus plant's soil.

Thrips

Keeping your hibisicus pest free is worth the time involved.

Healthy hibiscus buds will not discolor and fall from the plant, but if they are suffering from the ill treatment of thrips, the flowers will die before they bloom. A thrip is a small pest that lives and lays its eggs in many different types of flowers, including hibiscus. It looks like a tiny black line and is hard to see. The best way to determine if your hibiscus has thrips is to remove an open flower from the stem and shake it, upside down, over a piece of white paper. The insects are easy to see against the paper. To extinguish the infestation, remove all dead, unopened buds. Thrips mature in the soil under the plants they infest, so throw away all bud and flower droppings. Systemic insecticides can be used if you alternate types, because thrips quickly develop a resistance to chemical killers. For a more natural way to remove them, use a product containing neem oil.

References

• The World of Hibiscus: Pest Management
• All Experts: Hibiscus With Tiny Black Insects
• Flowers Growing: Hibiscus
• Hidden Valley Hibiscus: Hibiscus Pest Control

Resources

• Hidden Valley Hibiscus: Pruning Hibiscus