What To Spray On Garden Corn For Worms

Lynn has been a professional organic farmer for the last 35 years and runs a 210-acre farm in Western Colorado with her husband.

Corn earworms can ruin an entire crop of delicious sweet corn. Learn how to get rid of them without using any harsh chemicals.

Photo by Andre Ouellet on Unsplash

Gardening Without Harsh Chemicals

Do you love sweetcorn, but are leery of the chemicals that are sprayed on it twice a week to keep the corn earworm out? If you are like me, you don't want to feed your family any vegetables that are sprayed with chemicals.

Lucky for us, there are natural and organic ways to keep the corn earworm from destroying your delicious sweet corn crops.

Corn earworms destroy corn from the outside in, first eating holes in the leaves, then eating the silks, and finally munching right down into the kernels themselves.

Scot Nelson, Public Domain, via Flickr

4 Organic Ways to Get Rid of Corn Earworms

The corn earworm is one of the most destructive garden pests. It has four stages in its life cycle: egg, larvae, pupae, and moth. If you want an edible crop of corn, you will need to control the corn earworm. I like to control the pest at the larval stage.

Here are my four favorite ways to control the corn earworm.

1. Bt (Bacillus thuringiensis)

Bt is a bacterial pathogen that is used for biological control over larvae and is widely used by organic growers. Bt can work well if put on soon enough. Apply once a week to the corn ear as soon as you see the first silks.

It is not very effective once the earworm has entered into the ear. It is safe for plants, animals, and humans.

2. Diatomaceous Earth (DE)

Diatomaceous earth is ground-up fossilized seashells. It will puncture soft-bodied insects like corn earworms, causing them to dehydrate and die.

3. Captain Jack's Deadbug Brew

We use Captain Jack's Deadbug Brew once a week from the time that we see the first silks until we harvest the corn.

4. Drop Oil Into Each Ear of Corn

You can drop mineral oil, olive oil, or canola oil into the ears after the silks have turned brown. This will suffocate the worm, but will not affect the corn.

Corn earworm moths lay their eggs on corn crops.

Judy Gallagher, CC BY 2.0, via Wikimedia Commons

Corn Earworm Damage

The moth—about 1.5 inches long and grayish-brown in color with a few spots on the wings—flies around the garden, laying its eggs on the host plants. The larvae hatch out and start eating the corn plants.

First, they'll eat holes in the leaves as they are unfolding. Next, they'll eat the silks, which prevents the kernels from getting pollinated. Finally, the worm will bore down into the ears and eat the kernels down to the middle.

Happy Gardening!

With a few observation skills and some organic remedies, you can have worm-free corn to enjoy all summer long. May your garden be easy, fun, productive, and always organic!

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.