Cabbage worms are one of the most common and frustrating garden pests for any gardener. They’re annoying and will do lots of damage to your plants if you don’t react fast.
Cabbage worms are a broad term for a group of small green pest caterpillars, many of which are drawn to cabbage and mustard greens plant families. While noted for these plants, you can find these pests infesting broccoli, kale, collard greens, brussels sprouts, turnip greens, and even your flowers.
You will discover, these are larvae of small white butterflies that we often see around gardens. We know these as cabbage white butterflies most often or plain cabbage moths, even if they aren’t moths. A cabbage looper is a related caterpillar, which comes from a brown nocturnal moth.
You’ll find such cabbage loopers are like butterfly cabbage worms, although skinnier, and the green worms in plants hunch along like inchworms. (Find the Best Grub Worm Killer)
You can learn how to deal with a cabbage moth caterpillar in our guide and make sure there are no green worms in your garden eating your precious veggies. By the end, you’ll have countless methods of cabbage worm control you can try to see which has the best effect rather than covering your veggies with floating row covers.
How Do I Get Rid of Green Caterpillars on My Plants?
Many green worms in garden invade garden plants, including the imported cabbage worm. Luckily, control tactics designed for one type of worms, such as cabbage loopers, army worms, cutworms, or diamondback moth, are typically effective against all of them.
Early Growing Season
- You can discover there are many predatory bugs, such as spiders, yellow jackets, green lacewings, and parasitic wasps, that are some of the inch-long worm’s natural enemies. Cabbage worms are an immensely popular treat among birds. It is important not to use any chemical sprays that can harm either these insects or birds.
- To stop adults from laying eggs, use a floating row cover.
- To kill eggs, add Trichogramma wasps into your garden.
- Moths can be deterred from laying eggs on cabbage that has been sprayed with tansy oil. Companion planting tansy around the garden close to cabbage crops can be enough to keep pests away.
- Handpick caterpillars and eggs on the undersides of leaves and kill them once there is damage.
Late Growing Season
- Once worms are apparent, you can spread Garden Dust (Bt-kurstaki) onto the leaves you see activity. It is a naturally occurring soil bacteria and destroys the worms as they feed.
- Till in areas you have garden debris where overwintering pupae may attach themselves and emerge as adults in the early spring. In addition, the mustard family, and plants you have in the mustard need special attention since the cabbage worm pupae like to spend the winter in such areas.
- Worms can often cross garden boundaries and borders, so keep such areas clear to act as one of your winter pest control efforts.
Are Cabbage Worms Bad?
You see, these velvety green cabbage worms are roughly 1 1/2 inches long and have a faint light-yellow stripe across their back. Adults are the common white moths or cabbage white butterfly we see in the garden with black markings.
Imported cabbage worms (Pieris rapae) primarily eat anything that belongs to the Cole or cabbage family and can include broccoli, cauliflower, Bok Choy, Kale, and Brussels sprouts, among others. (Learn How Often Should You Water Vegetables)
Like other worms, these are savage foliage eaters and can contaminate what they don’t eat with their feces. Cabbage worms focus on cauliflower and broccoli after green cabbage.
How do I get rid of worms in my garden naturally?
If your imported cabbage worms (Pieris rapae), their eggs, or their fecal waste, then you should act right away. Leaving them to continue means you could lose your valuable crops.
Luckily, there are several organic and natural ways to get rid of cabbage worms in your garden.
- Combine 1/4 cup vinegar, 3 to 4 cups of water, and one teaspoon of dish soap into a mixing bowl.
- The soap helps the solution stick to the leaves.
- Spray the soapy water sparingly on the tops and the underside of leaves to prevent cabbage worms.
- If using this spray, be careful not to saturate the leaves, and the plants aren’t young seedlings.
Spray with Bt
Bacillus thuringiensis, better known as Bt, is an organic pesticide you can use to kill a variety of pests inside the garden. It is found naturally occurring in soil and used in organic gardening for many years.
Bt is toxic to the larvae of butterflies and moths and not harmful to birds or other mammals. It solves the issue to control cabbage worms and pests in the garden.
Use Bacillus thuringiensis on your plants every two weeks to kill off infestations, and if any worms remain, their numbers will be small, and you can pick them off or wash them off.
Spray with Neem Oil
Neem oil is an excellent natural pesticide used to kill caterpillars and soft-bodied pests you can find around your garden. You can spray it directly onto worms to kill them.
Neem oil can also be sprayed on the plants as this helps keep moths and butterflies from laying their eggs.
Remove Cabbage Worms by Hand
Picking the eggs and worms off your plant by hand can be a quick way to deal with the cabbage worm or their eggs.
The eggs are small, so it could be challenging to spot these tiny oblong eggs that are whitish or yellowish. If you see a group of tiny, oval white or yellow eggs, and these are laid bunched together, it sounds like these are ladybug eggs. (Read Tomato Hornworm Life Cycle)
Make sure not to pull these off or kill them as they are a natural enemy and one of the best beneficial insects you can have on your cabbage leaves.
Cornmeal offers many applications in your garden, including the control of cabbage worms. Simply spray your cabbage plants with water and generously sprinkle cornmeal on them. The worms consume the cornmeal, thus causing them to swell and die.
Ducks, chickens, and songbirds eat these worms; cabbage is favored by chicken, whereas ducks won’t touch your cabbage so long as they are mature plants. The concept for letting nature deal with nature is far better as it means you have less effort to deal with such pests. (Learn How to Keep Birds Away)
So, take up the chance to add a few ducks around your garden and even add that birdbath for the birds to start venturing into help.
How Do You Get Rid of Cabbage Moth Larvae?
The above methods are excellent for dealing with worms leaving holes in the leaves and preventing cabbage white butterflies from laying eggs as part of their life cycle.
Here are other ways you can deal with such white butterfly worms that invade your garden. (Read Tomato Plant Leaves Turning White)
Apply Diatomaceous Earth
You can get your hands on some food-grade diatomaceous earth and sprinkle this on your plants where cabbage worms have been seen. The diatomaceous earth powder quickly kills cabbage worms by piercing their bodies as they crawl across it. Diatomaceous earth powder is used to deal with many insects in varying areas around your garden.
Cabbage moths and butterflies may lay their eggs a few times throughout the year. However, during such times, you can set up row covers or netting barriers across your garden. Doing this keeps them away from your plants and thus stops cabbage whites laying their eggs. (Read Zucchini Leaves Turning White)
It may appear trouble, yet when you grow pest-repelling plants such as thyme, mint, and many other herbs close to your plants, you not only keep pests away, yet you increase plants and herbs you can use in your kitchen. Such herbs are often enough to stop adult butterflies and moths from laying eggs on garden crops.
Make Natural Repellent Spray
While you have the vinegar solution above, you can find many more natural ingredients, like garlic and cayenne pepper, to help deter cabbage worms. Mix said ingredients with water and create the repellent. Use a spray bottle and apply it to the underside of leaves. (Learn How to Make Natural Mosquito Repellent For Yard)
We have already seen how helpful birds and ladybugs can be. However, using beneficial insects is a sustainable approach to getting rid of cabbage worms. Such natural predators can include spiders, ground beetles, or praying mantis, along with things as birds and geckos, and many others.
Adding these is a great way to help you deal with cabbage loopers or the dreaded cabbage worm rather than resorting to dragging row covers on and off your crops all the time.