Whiteflies on peace lily
What's Happening
Whiteflies (Trialeurodes vaporariorum, Bemisia tabaci) are small sap-sucking insects that colonize peace lily foliage, particularly the undersides of leaves. These 1-2mm white insects feed on phloem sap, excreting honeydew that promotes sooty mold growth. Infestations typically occur when new plants introduce pests, or when plants are stressed by low humidity and poor air circulation. Whiteflies reproduce rapidly—females lay 200-400 eggs over their 4-week lifespan, with populations doubling every 7-10 days under optimal conditions (75-80°F, low humidity).
How to Fix It
- 1
Isolate infested plant immediately to prevent spread
- 2
Hose down foliage with strong water stream to dislodge adults and nymphs
- 3
Apply insecticidal soap or neem oil (azadirachtin 1% solution) weekly for 3-4 weeks, coating leaf undersides thoroughly
- 4
Introduce biological controls: Encarsia formosa parasitic wasps for greenhouse settings
- 5
Vacuum adults gently with handheld vacuum if infestation severe
How to Prevent It
Quarantine all new plants for 14 days and inspect undersides of leaves with 10x loupe before integrating into collection. Maintain 50-70% humidity with good air circulation to discourage whitefly establishment. Hang yellow sticky traps near plants to monitor for early detection. Avoid over-fertilizing with nitrogen, which produces succulent growth attractive to whiteflies.