Protecting Dinnerplate Hibiscus from Insect Defoliation: Preventive Spraying Schedule

The Problem

Hibiscus leaves are a magnet for Japanese beetles, sawflies, caterpillars. Lace-like damage = heavy feeding.

Prevention Protocol

1. Start 2 weeks after spring growth begins.
2. Apply preventive insecticide every 3 weeks through season — whether you see bugs or not.
3. Use concentrate (mix stronger than label) — more effective, less frequent than ready-to-spray.
4. Spray undersides of leaves — where insects hide.

Product Types

• Broad-spectrum (pyrethroids, neonicotinoids) — effective but harm pollinators.
• Targeted (Bt for caterpillars, spinosad for beetles) — safer.

Plant Health

The hibiscus itself is fine — it will return next year. Prevention starts early.