It all starts when a moth lays eggs on your plants, whether it’s a single egg or a cluster. A few days later, a caterpillar hatches. Finding a good repellent spray at this moment is vital before an infestation begins.
The caterpillar insect is the immature life stage of moths and butterflies. Typically, they are more of a problem for gardeners and can emerge in any color.
As it eats, it continues to grow, becoming a major pest for a range of plants, especially vegetables like kale, collards, cabbage, and all varieties of tomatoes.
If you detect them early, they’re much easier to control. Sure, you might see them hiding out behind leaves, but they might also be hard to spot. Look for ragged holes left in the plant foliage. That is a huge sign of leaf-eating worms.
Fortunately, there are quite a few home remedies that can stop them in their tracks. Below are 13 homemade spray recipes to keep caterpillars off your plants.
1. Insecticide Oil
An oil insecticide spray can repel caterpillars in the garden and a range of other pests, including mites, aphids, and more.
Mix 1 tablespoon of mild liquid soap with 1 cup of vegetable oil of your choice. When ready to apply, combine 2 teaspoons of the mixture with a quart of water. Shake well and spray directly on the plant.
2. Diatomaceous Earth
DE is a naturally occurring substance made from the fossilized remains of organisms called diatoms.
Diatomaceous earth has many uses; however, it makes a great caterpillar spray. Its abrasive qualities and incredible absorbing abilities allow it to dehydrate them.
Make a solution by combining 4 tablespoons of the product with 1 gallon of water. Shake until dissolved, and douse your plants.
When dry, it will leave a powdery residue, which is what will naturally kill caterpillars. You can also sprinkle the powder directly on the ground around your plants and on the foliage.
Use this simple concoction to make a natural spray for caterpillars, beetles, broccoli bugs, whiteflies, and more.
Mix 1 quart of water with 1.5 teaspoons of mild organic liquid soap. Shake well and spray directly on the affected area.
While soapy water does not kill caterpillars, it will encourage them to leave. Aim to apply it in the evenings or early mornings.
Garlic is an incredible pest control home remedy. The scent will repel all sorts of harmful insects from plants.
To make a natural caterpillar repellent using garlic, blend two whole garlic bulbs in half a cup of water. Next, let the mixture sit for at least 12 hours.
When it’s ready, add 1 teaspoon of mild liquid soap and a quart of water to the mixture. Mix well, strain, and then spray.
You can also combine this deterrent spray with hot peppers to get rid of armyworms and cabbage worms.
Vinegar is one of the best home remedies for making a pest control spray. Because of its acidic nature, it is used as a natural pesticide to kill many harmful insects.
To create a caterpillar killer spray that will not harm your plants, combine 2 tablespoons of raw vinegar with 4 liters of water. Shake well and apply to the affected areas.
6. Neem Oil
Neem oil is pressed from the seeds of the neem tree. Organic gardeners use it to get rid of all sorts of bad insects in all stages—from larvae to adults and everything in between.
To use neem oil to keep away caterpillars, combine 1 teaspoon of mild liquid soap, 2 teaspoons of neem oil, and 1 quart of water. Shake well and spray plants and visible pests.
7. Chili Pepper
You can use fresh peppers or chili pepper powder, which works quite similarly to garlic.
If you’re using fresh peppers, blend half a cup of chopped chili peppers in 1 cup of water. Next, add a quart of water and boil. Once cooled, strain and add a few drops of mild liquid soap before spraying.
If you’re using chili powder, mix 1 tablespoon with 1 quart of water and a few drops of liquid soap.
Citrus is effective at repelling soft-bodied insects.
To make a DIY spray for green caterpillars, grate the peel of a lemon or orange, add it to a pint of boiling water, and let the mixture sit overnight.
In the morning, strain through cheesecloth and spray the mixture onto the affected plants.
9. Chilli and Wormwood
This creative concoction can be used to discourage insects as well as possums and rabbits. However, you want the hotter varieties of chilies for it to be most effective.
Blend your chilies and wormwood in a cup of water. Once it’s all blended, add 5 cups of water and boil.
Let it stand until cool, then strain and spray the plants. However, keep the solution away from your eyes.
10. Organic Bacillus Thuringiensis Spray
Bacillus Thuringiensis (Bt) is a soil-dwelling bacterium that is used as a biological insecticide. It is toxic to gypsy moth caterpillars, tent caterpillars, tomato hornworms, and certain other insects.
Once the larvae ingest the Bt pesticide, feeding will stop and death will follow. However, it will not harm beneficial insects or birds.
Mix the recommended powder amount with water and coat the top and bottom of the leaves.
Some thick, gooey molasses will do the trick, fighting against all types of critters in your garden!
Mix 1 cup of molasses with 1 liter of water, then shake and diffuse all over your plants to help get rid of caterpillars naturally.
12. Hose ‘Em
This is the simplest and most straightforward option. After all, you’re likely out there with the hose watering your plants anyway!
Take a few minutes to blast those critters right out of the way.
Spray your plants directly, and as the green worms fall off, remove them and put them elsewhere, or kill them right away.
13. Tomato Leaf
The leaves of tomatoes can be a great way to get rid of pests.
Tomato plant leaves contain compounds that are toxic to aphids and other insects. When the leaves are crushed, these compounds are released.
Chop up 2 cups of tomato leaves and steep them in 1 quart of water. Leave overnight. In the morning, strain and spray your homemade insecticide all over your plants.
14. Coffee Grounds
Coffee grounds are also known to deter caterpillars. Therefore, make a spray by soaking half a cup of used coffee grounds in a gallon of water for at least 24 hours.
Afterwards, strain the solution and pour it into a spray bottle. Use this coffee grounds spray on garden plants and the caterpillars that you see.
15. Baking Soda
Baking soda has a plethora of garden uses, and insecticide is one of them. You can use it as a natural treatment for caterpillars and other insects.
For the recipe, mix one tablespoon of baking soda with a gallon of water. To make it work even better, add a teaspoon of liquid soap.
Shake well and thoroughly spray the infested plants.
If none of those DIY remedies catch your interest, you can purchase a ready-to-use natural product.
Below are our top 3 recommended caterpillar deterrent products that are safe for organic gardening use.
It contains the naturally occurring azadirachtin, a very potent compound derived from the neem tree.
Not only is it incredibly effective, but it’s safe for people, pets, birds, earthworms, and other harmless creatures.
Moreover, you can use it up until the day of harvest. Besides, it also works on trees, roses, and ferns.
2. Monterey Garden Insect Spray
Similar to Safer Brand, Monterey is a formulation product that is produced from fermentation. It contains spinosad, which is a substance made by a soil bacterium that is toxic to hairy caterpillars (higad), sawfly larvae, and other pests.
You can use it on your lawns, vegetable gardens, fruit trees, and much more. Furthermore, this organic caterpillar spray is fast-acting, odorless, and easy to use.
Diffuse onto the affected area to control cutworms, caterpillars, gypsy moth larvae, leaf miners, and more. You can also use it on edible plants such as basil, lettuce, broccoli, and cauliflower up until the day of harvest.
It is particularly useful if you have vegetables and fruits that you pick regularly.
3. JMS Stylet Oil
JMS is another fantastic brand. The company offers a range of solutions that are natural with botanically derived formulas, helping gardeners control pests and fungal plant diseases.
They have OMRI-listed pesticides, fungicides, and much more—products that are safe to use in organic farming.
Caterpillars will eat just about any plant, presenting a huge problem in your garden. Fortunately, there are ways to keep them away without using dangerous chemicals.
Whether you’re a DIY kind of person or you’d rather purchase a tried-and-true solution, there’s bound to be something on our list that will resolve your pest problem once and for all!