Cabbage Worm
Velvet-green caterpillars that match the leaf midrib they lie along, hatched from eggs laid by the white butterflies patrolling your brassicas. Ragged holes in cabbage, kale, and broccoli plus green pellet droppings down in the crown mean they are already at work.
Pest checklist
Four things to look for. If most of them match what you are holding, you are in the right place.
What gets rid of them
Gentlest option first. For most backyard cases the first one is enough, so try these in order and stop as soon as it works. If you do spray something, the product label tells you how — please read the notice further down.
1Row cover from transplant day
The butterfly cannot lay on what she cannot reach; covers stay on brassicas all season since they need no pollination.
floating row cover gardenTry this first2Hand-pick
Check leaf undersides and crowns twice a week; the green pellets point the way.
3Bt (Bacillus thuringiensis)
A biological that only caterpillars respond to; spray per label when picking cannot keep up.
bt spray caterpillars thuricide
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Which plants get cabbage worm
Every plant we cover that gets cabbage worm, grouped by type — tap any one to open its page. A note beside a plant came from that plant’s own entry, because the same pest can be a minor nuisance on one plant and a serious problem on another. Plenty of plants we do not cover get it too.
annuals11
Bok ChoyBrassica rapa subsp. chinensis
BroccoliBrassica oleracea var. italica
Brussels SproutsBrassica oleracea var. gemmifera
CabbageBrassica oleracea var. capitata
CauliflowerBrassica oleracea var. botrytis
Collard GreensBrassica oleracea var. viridis
KaleBrassica oleracea
KohlrabiBrassica oleracea var. gongylodes
Mustard GreensBrassica juncea
Napa Cabbage (Chinese Cabbage)Brassica rapa subsp. pekinensis
TurnipBrassica rapa subsp. rapa
Plant families hit hardest
Related plants often share the same problems, so if one plant in a family has it, check the others. The largest group here is Brassicaceae, with 14 of the 14 affected plants.
- Brassicaceae14 plants
When to treat
Start when the white butterflies show up, and check the undersides of leaves twice a week from then on.
On specific plants
- Growing
- Bt (Bacillus thuringiensis) every 7-10 days handles cabbage worms organically. Row cover from day one prevents most everything.
Timing only — the label is the law
This page tells you when to watch for cabbage worm and when treating is worth considering. It is not a recommendation to apply any particular product. Read and follow the product label before you spray — under federal law the label is the legal instruction, and using a pesticide against it is illegal.
- Check the pre-harvest interval. Every product that’s cleared for an edible crop sets a minimum number of days between spraying and picking. Find it on the label before you spray anything you intend to eat.
- Check the re-entry interval before you or anyone else works in the treated area again, and use the protective equipment the label names.
- Confirm the product is registered for your crop in your state. This page groups many different crops together, and a product legal on one of them is not legal on all of them — state registrations differ too. Your state pesticide agency or local extension office can confirm both.
- Rates and mixing instructions come from the label, never from us. We don’t publish them because they differ by product and formulation.
Other problems on the same plants
If a plant gets cabbage worm, these are the problems it most often gets as well, so they are worth checking for while you are out there. They tend to appear together; one does not cause another.