With cool, wet weather in Montana this spring, the insect populations have been under control in my own garden, but Im sure thats going to change very quickly. The one crop thats doing well is the cabbage, and Id like to keep it that way.

Last year, Samuel won his first Grand Champion Junior Exhibitor with an enormous Krautman cabbage. Of course, we have high hopes for this years fair exhibits, but he wont earn any blue ribbons if his cabbage is full of holes so were trying to stay on top of the pest situation.

Here are a few common cabbage pests throughout the country and what to do about them:

Cabbage looper (Trichnoplusia ni)

These are the cute little inch worms many of us played with as children. Theyre about an inch long and are light green with white stripes along the sides of their bodies. The adult moth is a brownish-grey and is typically active only at night. The damage occurs when the larvae chews through leaves and use the interior leaves as a latrine.

The easiest way to prevent infestation is to cover the cabbage with a fine netting or floating row cover in the spring. (When Sam informed me of the butterflies in the garden, I knew it was time to cover the cabbage.) If the moths cant reach the plants to lay their eggs you wont have the caterpillar.

The next option is to hand pick the little darlings. Theyre pretty easy to find, particularly when theyre larger and more active. Simply find and squish. If you have a lot of them, regular dustings of Bt (Bacillus thuringiensis) help keep large numbers under control.

Pests: Cabbage webworm (Hellula undalis)

This is a pest found in southern states all the way from Florida to California. The cabbage webworm does more damage to later planted crops rather than early spring crops, but this is a definite issue for gardeners who plant after the heat of the summer.

The caterpillar is a yellowish color with five purple stripes down its body. The more common telltale sign is webbing located along the inner leaves, as well as numerous damage from the webworm eating the leaves. If it burrows into the veins of the plant, it can kill it.

If youre going to use pesticides, do it as soon as you see the larvae or evidence of the webworms presence because they can effectively hide in the waxy leaves of the cabbage. Pyrethroids and Sevin work well. On a more organic front, dust with Bt at the first sign of their presence.

Cabbage maggots (Hylemya brassicae)

The adults look like regular houseflies, but its the larvae look like little maggots. They feed on the roots, which is why they can be extremely detrimental, if not fatal, to the cabbage plant. If your plants are withering and dying without another explanation, this could very well be the culprit. Check at the base of the plant to see if you can see the tiny, white maggots.

Cabbage maggots don’t do well in hot conditions. Planting through a fabric can help keep the adult fly from laying eggs at the base of the plant, as well as covering the crop in the early spring with a floating row cover. If you see the maggots at the base of the plant, mix a slurry of wood ash or red pepper and water the base. Theyre fairly vulnerable, and it should be enough to kill them. Be sure to move the location of your brassica crop and disc thoroughly to eliminate an overwintering generation.