Cabbage Pest Management

Joanne Whalen, Extension IPM Specialist, University of Delaware


General Sampling Plan : 5 plants in 10 locations up to 50 acres

Sampling Time Frame: 2 times per week

Pest Species

When to Sample

Action Threshold


Seedling Stage to Harvest - Infestations often spotty

2 % plants infested with 5 or more aphids per plant


Seedling Stage to Harvest - Watch for movement from field edges

20 % of the plants infested - need to catch before cupping

Flea Beetles

Cotyledon - Seedling Stage

One beetle per plant and "shothole" injury present


Cabbage Looper,

Imported Cabbageworm

Seedling Stage to Harvest *

Seedling Stage - Cupping: 20% infested **

Early Heading - Harvest : 5 % infested


* Note the species composition and size of larvae since chemical selection varies with species.

** Threshold is adjusted downward to 5% if larvae are feeding in the heart leaves.