I got a call some time ago from a reader about this worm in his cabbage. I visited his home to take a look.
Most of his cabbage and related crops had small holes in the leaves. He showed me the culprit: a green caterpillar about 1 to 2 inches long, with a thin line running from its thorax to its abdomen.
The reason that the insect was a butterfly was that it was a thin, small worm with the appendages and structures of a butterfly. My friend wanted to manage the insect organically.
As I was looking at the insects with him, he was picking these freeloaders off the cabbage leaves, which has been their primary approach to controlling them.
If you grow purple cabbage instead of green cabbage, you will find that these pests won’t bother your cabbage. Purple cabbage is mildly toxic to these caterpillars.
Recently, I have seen more gardeners using floating row covers installed over cabbage rows at specific times of the year to manage this insect. This insect is a nocturnal flier.
If you were to lay a fabric row cover over the cabbages, you may also find that, in the evening, you have controlled the insect. The cover prevents them from laying eggs on the plants and forces them to move to another location.
Old nylon stockings over the plant can also control insects, again because they can’t reach the plant.
Limiting access for Cabbage Moths is considered the best organic solution to managing this insect. This exclusion fabric will prevent damage from moths and birds and reduce frost damage.
Easy installation is one of the great pluses for this method. You use a combination of sleek hoops and insect netting. Keep in mind a row cover over your crops prevents pollination, which is OK for cabbage.
Over the years, I have done several things to control this insects. I have used Sevin with success, and one other thing confuses them. What I did was grind up 10 to 15 pieces of wormwood, Artemisia, or Dusty Miller in an old blender with a few cups of water and a little Joy dish soap.
Also, I have sprayed garlic oil over the plants to confuse the insects. I mixed in a tablespoon of Joy dish soap into the water and gently stirred the concoction.
The spray confuses the butterflies into thinking the cabbages are wormwood or garlic plants. The big challenge was spraying under the leaves where the insects really liked to feed, which is one of the tricks for solving the problem.
These insects tend to follow the veins of the plant but eat through the center of a cabbage head. The problem is that you have to be very thorough as you spray, because the insects can be very good at surviving if you don’t get the plant entirely.
Growing aromatic plants (hyssop, thyme, wormwood, celery, dill, sage, and onions) will all help confuse these insects.
Being a Master Gardener, I am also aware of the normal insecticides that are recommended to control this insect. Email me for more information.
One unusual way to deal with cabbage moth infestation is to make decoys. This pest is very territorial and won’t trespass on another moth’s territory. Decoys say this place is occupied.
The decoys are plastic green worms you can get at a toy store or bait store. These plastic worms are enough to confuse them when spread under the cabbage.
Bt (Bacillus thuringiensis), or Dipel, spreading once weekly, can also control these insects. This is more of a long-term solution, not for this year.
A small wasp by the name of Apanteles glomeratus can help, too. It lays its eggs in the caterpillar. These young wasps develop inside the caterpillar. Another biological control is a virus that attacks caterpillars, turning them gray and killing them.
Another natural solution for controlling these insects over time is to provide a habitat for birds that feed on them. You will need nest trees, alternative food sources, a water source, and cover trees near the garden. The birds will eat well.
Attracting Northern Mockingbird, Red-winged Blackbird, American Robin, and Northern Cardinal will enhance the elimination of the moth pest.
Solid organic solutions to many insect pests are available. Cabbage is too valuable for the freeloaders to rob us of the precious nutrients.
I hope you have a nice stroll through your garden this week. If you have any problems in your garden, e-mail me at ericlarson546@yahoo.com.