Controlling Honeydew and Sooty Mold on Crepe Myrtles and Understory Plants

Upright elephant ears planted under crepe myrtles became coated in sticky substance, raising concerns about plant respiration.

Cause

The sticky coating is honeydew excreted by aphids or scale insects feeding on the crepe myrtle. This sugar-rich substance promotes black sooty mold growth, which can interfere with photosynthesis on understory plants.

Solution

Apply Bayer Advanced Tree and Shrub Insect Control as a soil drench around the crepe myrtle. The systemic insecticide moves to leaves and twigs, killing sucking insects when they feed. This protects both the tree and understory plants without harming elephant ears. Effects take 1-2 weeks to reach canopy tops depending on tree size.