How to Kill Bugs on Cabbage

A cabbage plant is vulnerable to many different pests.

Aphids, cabbage maggots, and cabbage worms are a few of the insects that attack cabbage plants. Look for signs of bugs on your plants such as discoloration, wrinkled leaves, and holes caused by the bugs munching their way through the cabbage. The key to killing bugs for good is to spot them during the early stages of infestation.

Things You'll Need

• Ladybirds or green lacewing
• Garden hose
• Insecticide
• Malathion
• Yellow sticky traps
• Tinfoil
• Floating row covers
• Paper collars
• Methoxychlor
• Bacillus thuringiensis spores spray

Instructions

Aphids

1. Protect and encourage resident ladybirds or green lacewings, which prey on aphids. This is the natural way to get rid of them. Purchase predatory insects from your local garden store if necessary.

2. Wear protective gloves and remove aphids by hand.

3. Minimize aphid damage by blasting them with water from a garden hose. Pay attention to the head of the cabbage, where aphids tend to hide.

4. Apply insecticidal soap and malathion to the cabbage plant. Follow the manufacturer's directions for use. You can also make a nontoxic pesticide by mixing 1 cup of vegetable oil with 1 tbsp. of liquid dish soap. Mix 1 1/2 tsp. of the solution with 1 cup of warm water and pour it into a spray bottle. Spray the entire cabbage plant thoroughly, making sure you hit all visible aphids directly.

5. Position yellow sticky traps near infected plants to capture flying aphids.

6. Place sheets of tinfoil under the cabbage plants to reflect sunlight upward, which will help deter aphids.

Cabbage Maggots

1. Cover cabbage plants with floating row covers to keep flies from laying eggs near the plants.

2. Wrap 3-inch paper collars around each cabbage plant stem to create a protective barrier. Push the collars 1 inch into the soil to keep maggots that hatch on the stems out of the soil.

3. To get rid of adult flies, dust or spray plants with methoxychlor or malathion several times at 10- to 14-day intervals.

Cabbage Worms

1. Cover cabbage plants with floating row covers to keep butterflies (the cabbage worm in its adult stage) from laying eggs on them.

2. Put on protective gloves and pick off larvae by hand.

3. Spray larvae with spores of Bacillus thuringiensis, which is nontoxic to humans, animals, and other insects. Look for it in your local garden center. Repeat the process several times, every seven to 10 days.

References

• Oregon State University Extension Service: Don't Let the Bugs Beat You to It
• University of Kentucky College of Agriculture; Cabbage Insects; Ric Bessin; January 2004