How to Kill Whiteflies on a Poinsettia

Whiteflies feed on the sap of the poinsettias.

Whiteflies are small, white and generally found on the undersides of leaves. The pests live indoors on plants such as poinsettias because the warm temperatures gives them a place to thrive during the winter. The pests actually are not flies, but they have a similar appearance. When you notice whiteflies on your poinsettia, kill them as soon as possible to prevent the insects from damaging the plant or spreading to other indoor plants in your home.

Things You'll Need

• Yellow sticky traps
• Insecticide
• Washcloth
• Mild dish detergent

Instructions

1. Hang yellow sticky traps close to the plant to remove adult whiteflies. If the traps do not hang, you can lay them on a flat surface so that they are next to the plants. The traps will not destroy the whiteflies completely, but they help to control the population.

2. Apply an insecticide to the poinsettia to kill the whiteflies. Insecticides with imidacloprid, permethrin, resmethrin or pyrethrins work well at controlling whiteflies.

3. Wash the poinsettia plant with a washcloth dampened in a solution that consists of 1/2 teaspoon of a mild dish detergent mixed with 1 quart of warm water. Wipe the foliage with the washcloth to remove the whiteflies.

4. Remove leaves that are heavily infested with the whiteflies. Discard the leaves after you remove them.

Tips & Warnings

• Always examine plants before you bring them indoors to prevent whitefly infestations from occurring.

• Always read the instructions on pesticides carefully to prevent harming the poinsettia.

References

• Colorado State University; Greenhouse Whitefly; W.S. Cranshaw; January 2007
• Iowa State University; Check Your Houseplants for Whiteflies; Donald R. Lewis; January 2005
• University of Minnesota; Houseplant Insect Control; Jeffrey Hahn, et al.; 2005
• Government of Alberta; Whiteflies on Poinsettias; K. Pruski, et al.; October 1999