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Pest & Disease Library · Solutions

Gray Mold Control in Lettuce

Botrytis attacks lettuce at the base and outer leaves in cool, wet, humid conditions, rotting tissue and opening the door to secondary decay. It’s a common cause of field and post-harvest loss in dense plantings.

Common crops affected

Why it matters

It spreads from dying or wounded tissue and releases huge spore loads, so one infected fruit can rot a whole batch; sanitation and early protection are key.

When to act

Protect in cool, wet weather and dense canopies from heading onward.

What to look for

  • Water-soaked lesions on lower/outer leaves
  • Gray mould at the plant base
  • Collapse of affected leaves
  • Post-harvest rot in packed heads

How to manage it

  1. Remove dead and infected tissue; improve airflow and lower humidity.
  2. Handle fruit gently; cool quickly after harvest.
  3. Apply Spore Control (1:1,000) through cool, damp periods.

Recommended Vegalab program

Spore Control — encapsulated, adherent cover for rainfast protection.

RoleProductUse
Primary controlSpore ControlThymol; reduces inoculum on flowers & fruit
Firmness supportRigid BoostFirmer tissue resists invasion
Plant resilienceArmour BoostResilient tissue

Product claims, rates, and availability vary by jurisdiction; always follow the applicable label.

Frequently asked questions

How do I reduce it in the field?

Improve airflow and drainage and avoid dense over-fertilised canopies alongside treatment.