How to Treat a Whitefly Infestation on a Ficus

Ficus is an easy-care houseplant.

A wide range of Ficus species are easy-to-grow, warm-weather plants that do best indoors in most areas of the country. Depending on the type of Ficus, the plant may be a large tree, a vine or shrub. Fig trees are members of this huge plant family, as is the rubber tree. Indoors or outdoors, whiteflies can become a serious problem, causing the foliage to turn yellow or die. The insects are tiny and tend to collect on the undersides of the leaves. A simple test for the presence of whiteflies is to lightly shake some branches. If a cloud of tiny white specks erupts from the plant, it is infested with whiteflies.

Things You'll Need

• Garden hose or bathroom shower
• Small, handheld vacuum cleaner
• Plastic bags
• Yellow sticky tape or traps
• Insecticidal soap or horticultural oil
• Spray bottle or garden sprayer
• Insecticide

Instructions

1. Wash the foliage outdoors with a hard spray from a garden hose or place houseplants in the shower to knock off as many whiteflies as possible. The University of California's Integrated Pest Management website states that vacuuming the foliage can further reduce the whitefly population. Place a vacuum bag into a plastic bag and freeze it to kill the insects.

2. Place yellow sticky traps, available at most garden centers, around Ficus houseplants to capture whiteflies, which are attracted to the color. Follow manufacturer's directions for disposing of the traps.

3. Spray horticultural oil or insecticidal soap on houseplants and garden-grown Ficus to kill the whiteflies if washing them off does not eliminate the problem. Spray the undersides of the leaves, where whiteflies congregate and lay their eggs. Neem oil is less toxic to beneficial insects but kills whitefly nymphs and reduces egg laying. Make sure the product is labeled safe for houseplants if it is used indoors, and follow label directions for application frequency and dosage.

4. Spray the plants with a commercial insecticide. Look for products containing permethrin or pyrethrins, which are less toxic to beneficial insects, or products containing malathion or imidicloprid. Follow the label instructions for dosage.

Tips & Warnings

• Whiteflies on garden-grown Ficus are susceptible to several predatory insects such as spiders, minute pirate bugs, bigeyed bugs, lacewings and ladybugs. Some predators are available at garden centers, but they are vulnerable to insecticides.

• Whiteflies can develop resistance to chemical pesticides. Follow label directions carefully for best results.

References

• University of Illinois Extension; Ficus - Plant Palette; Jennifer Schultz Nelson
• University of California at Davis IPM: Whiteflies
• Missouri Botanical Garden: Whitefly - Indoors
• Missouri Botanical Garden: Whitefly - Outdoors
• University of Florida IFAS Extension: Ficus Whitefly Management in the Landscape

Resources

• Colorado State University Extension; Managing Houseplant Pests; W.S. Cranshaw
• University of Florida IFAS Extension; Got Dying Ficus? A New Species of Whiteflies Infesting Ficus in Miami-Dade County; Adrian Hunsberger and Henrique Mayer