Leaf Cutter

This damage is caused by leaf-cutter bees (Megachile spp.), which excise neat semi-circular pieces from leaf margins to line their nest cells, or by leaf-eating caterpillars (Lepidoptera larvae) that chew irregular holes through the lamina. It is not an infectious disease — the injury is purely mechanical feeding damage. Leaf-cutter bees rarely cause significant harm and are in fact valuable pollinators, but caterpillar populations can defoliate a plant rapidly if left unchecked.

Mechanical damage from a few leaf-cutter bees is best tolerated — they are important pollinators. Intervene only when a caterpillar population becomes established:

• Inspect the underside of leaves to locate young larvae.
• Hand-pick caterpillars or remove them with tweezers.
• Prune out and destroy heavily damaged foliage.
• Biological control: Spray Bacillus thuringiensis (Bt) for selective control of lepidopteran larvae without harming beneficial insects.
• Selective insecticides: For heavier infestations, apply Spinosad or Abamectin to knock down resistant populations.

• Scout the plant regularly, ideally in the early morning when caterpillars are still feeding openly.
• Drape fine mesh netting over the canopy in small home gardens to exclude both bees and ovipositing moths.