Lynn has been a professional organic farmer for the last 35 years and runs a 210-acre farm in Western Colorado with her husband.
How to Control and Prevent Cabbage Worms
Are their plants disappearing from your garden? Are there holes in the leaves? Are your plants sticky? You may have a pest problem in your garden, and pests can really plague a garden and prevent you from getting a good crop.
I've been a professional organic farmer for 35 years, and I've found some great ways to deal with all kinds of notorious garden pests that come around every year. Cabbage loopers (or cabbage worms) are part of our natural landscape here in western Colorado. They live on the whitetop weeds that we have around the farm, so there's no way of eliminating the loopers from my gardens.
The next best thing is to disrupt the worms' life cycle and stop their reproduction in the garden.
4 Ways to Stop Cabbage Loopers in Your Garden
Cabbage loopers (Trichoplusia ni) have four stages: eggs, worms, cocoons, and moths. I like to disrupt the cycle at the worm stage. Once I start to see the cabbage loopers flying around the farm and the garden, I start my control program and keep it up until after the third frost in the fall. Here are my four favorite methods for getting rid of cabbage worms.
1. DIY Citrus Spray
Caterpillars don't like the taste of citrus, so the bitter chemicals in this spray will run the caterpillars off. Apply once a week (and reapply if it rains). This citrus spray is super easy—and cheap!—to make.
- Grind up the rinds and seeds of any citrus fruit (e.g., oranges, lemons, limes, grapefruits, etc.).
- Add two cups of water and soak the mixture overnight.
- Strain out the pulp.
- Add 2 teaspoons of liquid soap to the mixture.
- Add to your sprayer and spray on the plant!
2. Captain Jack's Deadbug Brew
We use Captain Jack's Deadbug Brew once a week from the time we first see the white cabbage looper moths in the spring until our third hard frost. It's a great option if you don't have the time (or desire) to make your own spray.
3. Bt (Bacillus thuringiensis)
Bt is a bacterial pathogen that is used for biological control over larvae. It is widely used by organic growers, and I've used it with great success. It is safe for plants, animals, and humans.
4. Diatomaceous Earth (DE)
Diatomaceous earth is basically ground-up fossilized seashells. This sand-like mix punctures insects' bodies (both those with exoskeletons and soft-bodied ones like worms), causing them to dehydrate and die.
The key here is you need to get the diatomaceous earth where the worm can crawl through it, which is going to be up on the leaves in the case of cabbage loopers.
What's Eating My Plants?
If you can't figure out what is eating your plants, you want to go out at night with a flashlight and take a look at the garden—it's a whole other world at night! This is when many pests come out at night to eat. Here are some great tips about how to identify common leaf-eating pests.
With a little bit of detective work and some natural ingredients, you can have a pest-free garden.
Cabbage Harvest at The Living Farm
Struggling With Aphids?
Aphids are another one of those pests that like to make an appearance every year. Luckily, there are a few safe and natural ways to get rid of aphids too!
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2021 Lynn Gillespie