Identifying and Treating Scale and Mealybugs on Houseplants

What You're Seeing

• Hard brown spots: Scale insects (protected by hard shells).
• White fluff: Mealybugs (covered in cottony wax).
• Shiny sticky liquid: Honeydew—excreted by both pests.
• Black powdery coating: Sooty mold growing on honeydew.

Critical: Treat All Plants

Even plants without visible pests likely harbor eggs or crawlers. Isolate infested plants immediately.

Treatment Options

Systemic Insecticide (Best for Heavy Infestations)

• Spray-on systemics absorb into leaves, kill on contact, then provide lasting protection.
• Granular systemics are slower and less effective.
• Warning: Treated plants become toxic—keep away from children and pets.

Insecticidal Soap Spray (Non-Systemic)

1. Blast plants with strong water spray to remove insects/eggs.
2. Pick off visible pests with alcohol-dipped cotton swab or tweezers.
3. Spray mixture: distilled water + few drops dish soap + 3 tbsp 90% alcohol.
4. Cover all surfaces, especially leaf undersides.
5. Repeat every 5–7 days for ~6 weeks.

Prevention

Inspect plants weekly. Quarantine new plants. Act fast at first sign of pests.