Posts Tagged ‘controlling cabbageworms’

Cross-striped cabbageworm

Do I seem to be stuck in a rut?

Sorry but we’ve been getting some interesting questions on our discussion board lately and caterpillars seem to be a hot subject this time of the year!

Read on …

Hi, I am in Dutchess County, NY. Can you give me an idea as to what is eating my kale? Thanks!

Caterpillar damage on kale leaves

Caterpillar damage on kale leaves

First off, I must say that kale is a great vegetable! These tasty greens are packed full of excellent vitamins, minerals, and antioxidants. Because it’s so rich in nutrients, kale has been dubbed as one of the healthiest vegetables on the planet – the “queen of greens!” It is also very versatile and has many great uses in cooking and for using raw. Chopped kale is a great addition to soups and I always put in a big leaf or two when I make smoothies – de-lish!

Anyway, back to caterpillars because they’re certainly the critters eating her kale leaves. This picture she sent shows classic caterpillar damage.

Caterpillar damage on kohlrabi

Caterpillar damage on kohlrabi


Cabbage loopers, imported cabbageworms, and diamondback moth caterpillars are caterpillars that commonly feed on cole crops (plants in the cabbage family which includes kale). Other familiar members of this family are broccoli and cauliflower, Brussels sprouts, kohlrabi, and collards. All these plants are susceptible to attack by caterpillars.

Imported cabbageworm caterpillar

Imported cabbageworm caterpillar.
A cross-striped cabbageworm can be
seen in the background.

I have never tried growing kale but we have periodically tried growing broccoli and even Brussels sprouts in our garden.

These crops have never been very successful because of the whole caterpillar issue. We would usually get just one cutting of broccoli before caterpillars would explode all over the plants. The broccoli would become so disgusting with chewed leaves and frass (caterpillar poop) that we would just end up yanking them out.

The few times we tried growing Brussels sprouts, they became infested with aphids and caterpillars and never really produced buds – not that I think I would have eaten them even if they had. Don’t get me wrong, I love Brussels sprouts but not ones that have been sucked on by aphids and chewed on by little caterpillars! Can you tell we didn’t spray?

This early version was replaced by new row cover and a stronger frame.

This early version was replaced by new
row cover and a stronger frame.

Since cole crops don’t require pollination to produce a crop, one way to protect them from caterpillar damage is to cover them with a floating row cover to keep the adult butterflies (or moths in the case of the diamondback moth) from laying eggs on the plants. We tried that this year. I wasn’t going to grow broccoli but Eric wanted to try it one more time and use the floating row cover idea to protect the plants.

Here’s the thing, though. You have to put the row cover over the plants before the eggs are laid!

Imported cabbageworm butterfly

Imported cabbageworm butterfly

We had it well sealed so that no adults could get inside but there must have been eggs or tiny caterpillars already on the plants because after a month or so, there were quite a few cabbageworm butterflies fluttering around inside our row cover tent. Oops!

Needless to say, the broccoli plants had been ravaged by the caterpillars and I yanked them all out – again!
I think we will just buy broccoli at the grocery store from now on!

Cross-striped cabbageworm and frass on broccoli

Three cross-striped cabbageworms
and lots of frass on broccoli

If we DO ever try growing it again, I will begin spraying early with Bt (Bacillus thuringiensis) or Bonide Captain Jack’s Deadbug Brew (spinosad). These are two organic controls that I have mentioned before for killing caterpillars while being kind to beneficials.

The other option is hand picking; but in my experience, the sheer numbers of these caterpillars make this control method impractical and in addition, since most of the common ones are green, they are well camouflaged and hard to find!

On another note, I think I may try growing some kale in our lettuce containers on the deck this fall – just for a test. The deck is pretty sheltered and I can cover the containers with plastic if necessary as it grows colder. It will be an interesting experiment. It may be too late but I think it is worth a try.

I’ll keep you posted!

Until next time – Happy Gardening!

Read Full Post »

%d bloggers like this: