Never do today what you can pay your kids to do tomorrow. It is sage advice that has been passed down for millenia. Last week, I employed it.

I had been running around the yard in pursuit of white butterflies, the ones that lay eggs on the leaves of plants in the brassica family, the cole crops: cabbage, broccoli, cauliflower, kale, collards, etc. The eggs of the white butterflies hatch into green caterpillars that feed on the leaves.

They start out tiny, and they eat tiny holes.

But they grow rapidly and soon eat large holes. On a broccoli seedling, the caterpillar can eat so much of the leaves that the plant dies. On a larger cabbage plant, the caterpillar likes to eat into the head, leaving scatterings of green poop behind its tunnel and ruining the harvest.

The name of this caterpillar is Pieris rapae, and it is sometimes called “imported cabbageworm” or just “cabbage worm.”

There is a similar caterpillar that feeds on cole crops called the cabbage looper, but it has white stripes on its back and moves like an inch worm. It also does not turn into a pretty butterfly but rather a drab-colored moth. The cabbage looper damages your cole crops all the same, however, and can be dealt with using most of the same techniques as for the cabbage worm.

Techniques

I use a three-pronged approach to minimizing the damage that can be caused by cabbage worms (and loopers). First, I keep an eye out for holes in leaves. If I spot any, then I look around the plant to find the caterpillar eating the holes. It can be found anywhere on a leaf: on the top or bottom, near the rib or edge, even in the rosette. They blend in very well.

I usually pick them off and throw them.

Second, I look for eggs. This is especially good to do for seedlings because they can’t tolerate much damage so it’s best to eliminate the eggs before they hatch.

The eggs are whitish or light yellow, laid in singles, and they look like tiny cones stuck onto the leaves. They can be on the top or bottom of leaves. Just wipe them off.

The third prong yields even more benefits than wiping off eggs. The third prong is catching butterflies. Catching one butterfly is worth wiping off dozens of eggs because it prevents the laying of dozens more eggs.

If only the butterflies were easier to catch . . .

Pay the kids

Last week, I had clapped a few butterflies in middair, and that felt satisfying, but it took much time and many misses. One of my sons has a net that he uses to catch bees, I recalled. We refrigerate the bees to put them to sleep so we can look at them closely. They slowly wake back up and fly off unharmed. I grabbed his net and caught a few butterflies more easily. That was smart, but my next idea was smarter:

“Miles, I’ll give you a dollar for each white butterfly you can catch!”

“Why do you want to catch butterflies?” he asked.

I told him that I only wanted to catch the white ones, I showed him the eggs and caterpillars that they come from, and I showed him the holes they ate in our cole crops. He then understood why we had to reduce their numbers. He was off and running, and he came back with one in the net shortly.

Then I heard him recruiting his younger sister as a scout.

“You helping Miles find butterflies?” I asked her.

“Yeah, he said he’d give me Pokemon.”

“Oh, nice.”

“A card that does 60 damage!”

“Nice!”

My wife thinks I am overpaying them, but I bet she won’t be complaining when our cabbage heads are clean and whole.

Bt

An alternative approach is spraying with a pesticide that contains the bacterium called Bacillus thuringiensis, or Bt for short. Monterey makes this Bt spray. I’ve never tried this, but I read that it is effective at killing the cabbage worms.

However, it has downsides. One is that it kills all other caterpillars too. I don’t want to kill all caterpillars, just the ones that are eating our food.

Row covers

You can also prevent the butterflies from accessing your plants with a row cover.

“Dad, I caught another one!” Miles shouted through the window just now as I was writing this post. Never do today what you can pay your kids to do tomorrow.

Thank you for your support of my Yard Posts.

All of my Yard Posts are listed HERE