How To Prevent and Get Rid Of Cabbage Worms on Brassicas

Cabbage worms can wreak havoc on many types of plants, including brassicas. If you’re trying to grow a beautiful garden and it’s covered with larvae, eggs, worms, and moths, you’ll have a difficult time getting anything edible out of it. The good news is there are many ways to keep them from coming back next year.

Cabbage Worm

To prevent and get rid of cabbage worms on brassicas, you can protect them with floating row mesh covers, remove the eggs and larvae by hand, and if further protection is necessary you can add neem oil or use other organic pest control methods.

In this post, we’ll cover the step-by-step method to get rid of cabbage worms once and for all. We’ll also show you a handful of suggestions to keep them at bay and prevent them from making a home out of your garden. Enjoy!

What Are Cabbage Worms?

Cabbage worms are the green larvae of the “Cabbage Whites” Butterfly. They are a common pest of many plants in the cabbage family. When you see the small white butterflies fluttering around the garden these beautiful butterflies are actually laying eggs on the bottom side of the plant leaves.

Cabbage moth and worms

Use Floating Row Covers to Protect the Brassicas

Floating row covers are some of the most effective tools used against cabbage worms and other invasive insects. These rows are made of multiple curved pieces that hang over the brassicas. They’re covered with a thin mesh layer that you can see through without letting the bugs inside.

You can build your own floating row covers or buy them at a local gardening store. Either way, you’ll enjoy a beautiful garden without a bunch of cabbage worms tearing everything apart. It’s one of the most useful methods for people who don’t want to remove the insects by hand every week manually.

Floating row covers are breathable, too. This process lets them get all of the sunlight, water, and oxygen your brassicas need to live a long, healthy life cycle. You can harvest them by removing the corner of each row and lifting the thin mesh layer.

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Last update on 2024-06-13 / Affiliate links / Images from Amazon Product Advertising API

Remove Excess Cabbage Worms by Hand

The Farmer’s Almanac explains how effective manual removal can be. If your garden is overwhelmed by cabbage worms, eggs, moths, and worms, it’s time to take action. Clearing the bulk of them can make it much easier to get rid of them and prevent them from coming back.

Before you get started, put on a pair of gloves. These nasty pests can squish when you grab them, and you don’t want that mess on your hands! Furthermore, it’ll let you hold a handful of them without going back and forth to the yard waste bin. Never throw cabbage worms into the grass or another part of your yard; They’ll find their way back!

When you’re removing cabbage worms by hand, don’t forget to look under the leaves. They often hang around in the shadows since it provides concealment and food.

Focus On Removing the Eggs

Cabbage worm eggs are a problematic part of the equation. While they might seem relatively harmless, they’re the future generations of worms that’ll destroy your garden.

The good news is many cabbage worm eggs are sitting in plain view. These small yellow-green eggs look like tiny dots all over the brassicas. Wipe them off with a glove or spray them with neem oil. Both solutions will be effective enough to prevent them from hatching and turning into plant-eating cabbage worms.

Attract Beneficial Insects

In true permaculture fashion, it is always best to bring balance to the life in your garden. When you have a destructive insect you can usually balance the problem by introducing predators of the insect to the garden naturally.

The Braconid Wasp is a natural predator of the cabbage worm and this wasp can be attracted to your garden by introducing plants that will attract it. These wasps are attracted to flowers and herbs that produce small florets such as sweet alyssum, dill, chamomile, feverfew, fennel, catnip, and buckwheat.

Attract Birds That Prey On Cabbage Moths

Sparrows, Skylarks, and Finches will eat any cabbage worms they can find so inviting these birds to your garden can help you fight the war on your brassicas. Having birdbaths, and houses in your garden will invite then beneficial bird predators where you want them.

Sparrow in garden

Sprinkle Cornmeal on the Brassicas

While it might seem strange, cornmeal is an affordable and simple trick to get rid of cabbage worms on your brassicas. You can wash your plants and sprinkle a bit of cornmeal all over them. The cabbage worms and larvae will eat the cornmeal, become bloated, and die.

This effective treatment doesn’t require any chemicals, but it’s a good idea to wash the brassicas to remove excess cornmeal when you’re done. It can dry on the leaves and become tricky to get rid of when it’s time to harvest and eat them.

Organic But Last Resort Options

These next options I consider as last resort options. Even though they are considered organic options I don’t necessarily think adding them to the garden is the best option, especially for a permaculture garden. I do include them though because sometimes having a yield is more important than the little harm they can cause.

The main reason I consider them a last resort option is because they can kill or cause harm to more than just the destructive insect you are trying to kill. Whenever you add something to your garden that can do this it can cause an imbalance in your garden. There are some insects you want to keep but sprays don’t discriminate.

Consider Neem Oil Sprays

Neem oil is another highly effective treatment for cabbage worms and similar bugs that feast on your brassicas. Spraying a thin layer of neem oil on and around your plants will keep them out of harm’s way without causing problems for you, your pets, or your garden. It’ll also repel a host of other pests without killing them.

The Bonide Ready-to-Use Neem Oil is an excellent example of a quick and easy way to handle the problem. This compact spray bottle comes with enough neem oil to treat a garden several times. It’s important to spray it around the plant and under the leaves. Anywhere the oil goes, cabbage worms won’t!

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Last update on 2024-06-12 / Affiliate links / Images from Amazon Product Advertising API

Apply B.T. Once Every Two Weeks

If you’re looking for a quick and easy solution for cabbage worms eating your brassicas, try the Monterey Bacillus Thuringiensis (B.t.) Worm & Caterpillar Killer. Mix it with water and spray it all over your garden for a natural, long-lasting shield from cabbage worms, moths, and other pests that keep eating the leaves and stems.

Btk is effective because it contains ingredients that naturally repel many insects. Most Btk solutions are approved to be used in organic gardens, allowing you to maintain a healthy lifestyle while enjoying fruits and veggies without loads of holes in them. It’s also safe to use around ladybugs, bees, and other bugs that are beneficial to the local ecosystem.

The primary ingredient (Bacillus Thuringiensis) spreads spores all over the plants. Thankfully, they won’t harm you or your pets. Simply wash the food before preparing it for a meal to get rid of the taste.

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Last update on 2024-06-13 / Affiliate links / Images from Amazon Product Advertising API


Protecting your brassicas from cabbage worms is much easier than you might’ve thought. Especially if you prevent the problem in the first place by covering your crops. Many natural sprays can protect your plants without damaging them with unsafe chemicals. Furthermore, removing the eggs and larvae will stop future generations from growing on and eating your garden.


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    Author, blogger, podcaster, homesteading and permaculture enthusiast. I have a passion for sharing what I learn and helping others on their journey. If you're looking for me, you'll usually find me in the garden.

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