Caterpillars on Hibiscus and Peppers: Organic Bt Control

Inchworms on hibiscus and a large caterpillar on peppers—both are lepidopteran larvae. The best organic tool is Bacillus thuringiensis (Bt).

How to Use Bt

• Buy Dipel (dust) or Thuricide (liquid concentrate).
• Apply when caterpillars are small; cover leaf undersides thoroughly.
• Reapply after rain or every 7–10 days until harvest.
• Safe for humans, pets, bees, and beneficials.

Why Not Soap or Water?

Insecticidal soap works on soft-bodied insects (aphids, mites) but is less effective on caterpillars. Water blasts dislodge but don't kill.

Companion Planting

Plant dill, fennel, or parsley nearby to attract parasitic wasps that target caterpillars.

Bt is the gold standard for organic caterpillar control on edibles and ornamentals.