Controlling Whiteflies and Fungus Gnats on Indoor Hibiscus

Controlling Whiteflies and Fungus Gnats on Indoor Hibiscus

Moving a hibiscus indoors for winter brought small black flies (fungus gnats) and tiny white spots (whiteflies) on leaves.

Effective Treatments

• Insecticidal soaps/oils: Highly effective for both pests; available at nurseries.
• Mosquito dunks (Bti): Float a dunk in water overnight, then water plants. The bacillus kills gnat larvae.
• Knock Out Gnats: Commercial product for gnat control.

Prevention

Inspect new plants before bringing them inside. Allow soil to dry between waterings to discourage gnats. Quarantine new additions.

For more specialized advice, consult a houseplant forum.