Hibiscus plants are members of the Malvaceae family. One of the most popular shrubs of the tropics, according to the University of Florida, most hibiscus form large blossoms that last just one day. The flowers bloom in a multitude of shades, including red, lavender, orange and yellow. While there are numerous varieties of hibiscus plants, all are susceptible to certain pests that can cause holes in the leaves.
Hibiscus leaves with holes in the center usually are the result of snails, slugs, leafminers and cutworms. The holes may appear as rounded spots or tunnels across the inner areas of the leaves. They can occur when adult flying insects lay their eggs on the undersides or bases of the leaves. As the larvae hatch, they begin eating the vegetative growth. This condition can be self-limiting, resolving when the larvae pupate stop feeding. If the holes are a result of feeding of snails, beetles and slugs, the infested hibiscus may require treatment to resolve the condition, especially if the damage is extensive.
Caterpillars are the most likely culprit in causing holes with leaves that form along outer edges. As with some varieties of leafminers, caterpillars hatch and begin feeding on the host plant. Leaves may appear ragged and chewed around the perimeter. Caterpillars may eat the entire leaf before they move to other areas of foliage.
Hibiscus plants generally tolerate minor foliage feeding without any problems. Large infestations can lead to a loss of vigor, which usually occurs when the leaves begin to turn yellow and drop. Fungal and bacterial infections can be responsible for some of the damage to the health of the plant. The nematodes often enter the plant in the weakened and damaged portions of the leaves.
Immediate pruning of the damaged foliage is the first step in protecting the health of the affected hibiscus plant. Providing proper irrigation and fertilization also helps boosts the heath and helps to reduce damage from pests. Hibiscus plants prefer well-drained soils with a pH level of 5.5 to 6.5. Watering once a week during droughts helps keep the soil slightly moist near the roots. Three or four feedings each year with a 15-5-10 fertilizer can help protect the health of hibiscus plants.