Mealybugs on calathea
What's Happening
Mealybugs (Pseudococcidae) target Calathea's tender new growth and leaf axils where they feed on sap and excrete honeydew. The pests appear as white, cottony masses in leaf joints and along stems. Unlike spider mites that cause stippling, mealybugs cause yellowing, stunted growth, and sooty mold from honeydew. Calathea's dense foliage provides excellent hiding spots. Infestations often begin on new growth and spread to mature leaves.
How to Fix It
- 1
Isolate infested plant immediately
- 2
Remove visible mealybugs with cotton swab dipped in 70% isopropyl alcohol
- 3
Spray with insecticidal soap or neem oil, targeting leaf axils and undersides
- 4
Apply systemic insecticide granules to soil for long-term protection
- 5
Repeat treatment every 5-7 days for 3-4 cycles to catch newly hatched nymphs
What You'll Need
How to Prevent It
Inspect new plants thoroughly before purchase, especially leaf axils. Quarantine new plants 14 days. Maintain plant health - stressed plants are more susceptible. Avoid over-fertilizing which produces tender growth mealybugs prefer.