Ants on Broccoli Plants: Symptom of Underlying Disease, Not the Cause

A first-time broccoli grower finds ants underground around fallen plants. Other vegetables are unaffected. Garden soap and Sevin dust were applied.

Expert Answer: Ants alone don't harm plants. Their presence suggests the plants are exuding sap (sugar water) due to disease—likely fungal or bacterial. Eliminating ants won't fix the problem; the disease must be treated. Consult your county Extension Master Gardeners for local plant disease advice.

— Jack DeAngelis