How to Get Rid of Caterpillars in Your Yard

Caterpillars are cute, especially the ones that morph into the exquisite butterflies we all know and love. But you’ll think otherwise when you see the destruction these critters can inflict on your precious yard. Here, you’ll learn how to get rid of caterpillars in your yard, as well as the signs of a caterpillar infestation and how you can prevent it.

How to get rid of caterpillars in your yard

With their voracious appetites, these insects can quickly become a nuisance in your yard. Before turning into beautiful butterflies, they can wreak havoc on your beloved plants and trees. So, follow these steps to banish those leaf-munching invaders from your outdoor oasis:

Step 1: Identify the type of caterpillar in your yard

Before taking action, identify the specific caterpillar species infesting your yard. Different species may require different eradication methods. Common culprits include the tomato hornworm, gypsy moth, and tent caterpillar.

Here’s how to identify them:

• Observe the pests and plants: Note their size, color, markings, and any distinguishing features. They can range from tiny and green to large and brightly colored.
• Identify the host plants: Consult field guides or reputable online resources. Different species have specific larval host plants they prefer. For example, tomato hornworms are often found on tomato plants, while the monarch species feed exclusively on milkweed.
• Consult a local expert: Reach out to local gardening clubs, entomologists, or agricultural extension offices for assistance. Local experts may have specific knowledge about common species in your region and can provide guidance.
• Use an app: There are smartphone apps available that can help identify the species by uploading photos of the insects. Apps like iNaturalist are user-friendly and can provide accurate identifications.
• Collect a sample: If you’re still uncertain about the species, consider collecting a sample. Place the insect in a container with ventilation holes and provide it with a few leaves of its host plant. This can help you observe its development and behavior, which may aid in identification.

Why identifying the caterpillar species matters

Identifying the type of caterpillar is crucial because it helps you determine the right approach to pest control and management. They respond differently to control methods, and some species may be more destructive than others. For example:

• Some species are easily controlled by hand-picking or using natural predators.
• Certain species may be resistant to specific insecticides, so choosing the right product is essential.
• Knowing the host plant can help you focus your efforts on protecting vulnerable plants.
• Identifying the species allows you to implement preventive measures tailored to the species’ habits and life cycle.

Step 2: Choose the caterpillar control method

Once you’ve identified the species and assessed the extent of the infestation in your yard, it’s time to select the most suitable solution. Control methods can vary in their effectiveness, environmental impact, and ease of implementation.

Here are four common approaches, each with its own benefits and considerations:

1. Remove caterpillars by hand

You may opt to physically remove the insects from your plants. Wear gloves and inspect your foliage regularly. Pluck the caterpillars from the leaves and deposit them into a bucket of soapy water. 

Hand-picking the insects is a precise and environmentally friendly method. It’s particularly effective for small infestations and allows you to target specific plants.

Note: The following insects are especially harmful if you don’t wear gloves when removing them:

• Armyworms
• Bagworms
• Gypsy moth larvae
• Tomato hornworms

Step-by-step method to remove caterpillars by hand

1. Wear gloves: Wear gardening gloves to protect your hands from insect hairs, which can sometimes cause skin irritation.
2. Inspect plants: Regularly inspect your plants, especially the undersides of leaves, where these insects often hide.
3. Pick them off: Gently pluck them from the plant and place them in a container filled with soapy water, which will drown and kill them. Use a solution of about a half bucket of hot water and 2 tablespoons of mild dish soap.
4. Remove their eggs: Lift plant leaves and check the undersides for caterpillar eggs.
5. Repeat: Continue this process regularly.

2. Use natural insecticides

Avoid harmful insecticides that might kill beneficial insects and pollinators, such as bees and butterflies. Natural insecticides are environmentally friendly and pose minimal risk to beneficial insects, birds, and wildlife.

For larger infestations, consider using natural pesticides like neem oil, Bacillus thuringiensis (BT), or diatomaceous earth. These eco-friendly solutions can deter pests without harming beneficial insects or the environment.

Neem oil

A natural way of killing garden pests like cabbage worms and tomato worms, neem oil does so within a few hours. Mix 2 ounces of neem oil per gallon of warm water. Then, spray the solution directly onto the insects and affected plants.

Organic BT

This compound occurs naturally in soil and contains a protein toxic to garden pests like hair caterpillars and mosquito larvae. It breaks down in their gut, infecting and starving them until they ultimately die. Apply directly to garden plants and reapply weekly as they return.

DIY control solutions

You can create a DIY solution using a number of ingredients you probably already have in your kitchen.

Pepper and garlic mixture: It kills garden pests as well as other plant-eating worms, aphids, and cabbage moths. Blend the following ingredients together and let the mixture sit for 24 hours:

• 1 tablespoon of dried red pepper flakes
• 1 bulb of minced garlic
• 1 teaspoon of mild dish soap
• 1 gallon of water

Chili spray: It will deter caterpillars from munching but should be applied to a small section of the plant first to ensure there are no adverse effects. Stir the following ingredients together well, and let sit and cool for a few hours:

• 7 tablespoons of ground chili pepper
• 1/2 gallon of boiling water
• 1/2 gallon of cold water
• 2 to 3 drops of mild dish soap

Vinegar solution: It works as a natural insecticide and pesticide, deterring various insects and garden pests. It also can eradicate slugs and snails. Mix the following ingredients together and use a spray bottle to apply wherever you see butterfly larvae:

• 2 tablespoons of vinegar
• 1 gallon of water

Step-by-step method for using natural insecticides

1. Identify the right product: Choose a natural insecticide suitable for the specific species you’re dealing with.
2. Follow instructions: Read and follow the product’s instructions for mixing and application carefully.
3. Apply thoroughly: Spray or dust the affected plants, including the undersides of leaves, where these pests often feed and hide.
4. Repeat as needed: Depending on the product, you may need to reapply it periodically or after rainfall.

Note: While natural insecticides are generally safe for humans and pets, follow safety precautions and avoid spraying during windy conditions to prevent unintended harm.

3. Modify caterpillar habitats

Make your yard less inviting to garden pests by reducing their preferred hiding spots:

• Prune overgrown branches where these insects might pupate.
• Remove fallen leaves, branches, and plant debris from your yard, as these can provide hiding places for caterpillars and pupae.
• Install a birdhouse with feed near affected plants and trees. Birds love crawling insects, along with sawflies and their larvae. However, this isn’t a good option around fruit trees, as it may entice the birds to eat the fruits.
• Wrap a 12-inch-tall piece of burlap around trees. Fasten the burlap to the tree with twine. Drop the top half of the burlap over the twine and let it hang over the bottom half. Watch these pests accumulate underneath the shade of the burlap during the heat of the day, and then collect and remove them by hand.
• Place physical barriers like copper tape or sticky tree bands around the trunks of trees and shrubs to prevent these crawling insects from accessing leaves.

4. Use row covers

An effective pest control method, using row covers can protect your plants without relying on chemical pesticides. These covers are typically made of lightweight, fine-mesh fabrics, such as polyester or nylon, and serve as a physical barrier that prevents these insects from reaching your plants while still allowing sunlight, rain, and air to pass through.

Here’s the step-by-step method for using row covers:

1. Select the right type: Choose between floating row covers or tunnel row covers, depending on your garden layout and plant types.
2. Measure and prepare: Measure the area to be covered and cut the row cover material to size.
3. Install and secure: Drape the row cover over your plants, securing the edges with garden staples, rocks, or other weights.
4. Monitor and maintain: Regularly inspect the row covers for damage or gaps, repairing any issues promptly.

Step 3: Opt for caterpillar-repellent plants

An effective and natural way to deter these garden insects from infesting your yard is by using repellent plants. These plants contain compounds, such as essential oils or chemicals, that are toxic to these insects.

This method is eco-friendly, as it avoids using chemical insecticides that can harm beneficial insects. Additionally, many repellent plants are attractive additions to your garden, contributing to the overall visual appeal of your landscape. For this step, do the following:

1. Identify repellent plants: Research and identify plants known to repel caterpillars or are less attractive to them. Common examples include marigolds, chrysanthemums, garlic, and catnip.
2. Choose appropriate locations: Determine where in your yard you want to plant these repellent species. Consider areas prone to caterpillar infestations or those with valuable plants you wish to protect.
3. Companion planting: Plant repellent species like peppermint, lavender, mugwort, and sage alongside your susceptible plants. The presence of these deterrents can discourage the pests from settling nearby.
4. Maintain healthy plants: Keep your repellent plants healthy and well-maintained. Proper care, including watering and occasional pruning, helps maximize their effectiveness.

Pro tip: Consider incorporating native plants into your garden, as they are often well-adapted to local conditions and less susceptible to pest infestations. Also, plant nectar-rich flowers to provide beneficial insects like ladybugs, lacewings, and parasitic wasps with food sources.

Step 4: Maintain a healthy garden

Regularly water, prune, fertilize, and mulch to keep your yard thriving. A well-maintained garden not only enhances the visual appeal of your yard but also plays a vital role in deterring insects. Healthy plants are more resilient and less likely to attract or succumb to infestations.

Apart from using compost to enrich your soil naturally and enhance plant vitality, you also must do the following:

1. Water properly: Ensure your plants receive adequate and consistent watering. Drought-stressed plants are more vulnerable to insect damage.
2. Fertilize appropriately: Overfertilization can lead to excessive growth. Use organic, slow-release fertilizers to provide essential nutrients to your plants.
3. Apply mulch: Apply mulch around the base of your plants to retain moisture, regulate soil temperature, and reduce weed competition. Mulch also discourages these pests from pupating in the soil.
4. Prune and deadhead: Regularly prune dead or diseased branches and deadhead spent flowers. This not only improves the plant’s appearance but also reduces hiding places for pests.
5. Monitor pests: Keep an eye on your garden for signs of infestations. Early detection allows for swift action to prevent widespread damage.

Signs of a caterpillar infestation

Detecting a caterpillar infestation early is crucial for effective pest control. Some types of caterpillars are brightly colored and stick out like sore thumbs on the green foliage of plants. Others may blend in with the surroundings or simply just don’t come out during the day.

Here are some common ways to tell if you have a caterpillar problem:

• Chewed or skeletonized leaves: These pests are voracious eaters, and one of the most noticeable signs of their presence is the appearance of leaves that have been partially or entirely consumed. You may observe irregular holes, ragged edges, or even complete defoliation on your plants.
• Visible caterpillars: In some cases, caterpillars themselves may be visible on your plants. These larvae vary in size, shape, and color, depending on the species. Some species may blend in with the foliage, while others have distinctive markings.
• Fecal droppings (frass): Caterpillars excrete waste as they feed, and this can accumulate on the leaves and around the base of plants. These small, pellet-like droppings are an indicator of their presence.
• Silken threads or webbing: Certain species, like tent caterpillars and sod webworms, create silken threads or webbing as they build protective nests in trees or shrubs. These webs can be a clear sign of infestation.
• Damaged fruits: If you have fruit-bearing plants or trees, these pests may target the fruit as well. They can leave behind scars, holes, or tunnels in the fruit’s flesh.
• Stunted growth: Caterpillar feeding can hinder the growth and development of plants. If you notice that your plants are not thriving as expected, it may indicate an infestation.
• Presence of natural predators: Sometimes, the presence of natural predators such as birds, ladybugs, or parasitic wasps can be an indirect sign of caterpillar infestation. These predators are drawn to your yard by the abundance of caterpillars.
• Caterpillar eggs: In some cases, you may discover clusters of small, oval-shaped eggs attached to the undersides of leaves or stems of host plants. These eggs can hatch into hungry caterpillars if left unchecked.
• Nighttime activity: Some species, like cutworms, are nocturnal and feed primarily at night. To detect them, you might need to inspect your plants after dark with a flashlight.

How to prevent caterpillars in your yard

It’s better to prevent different species of caterpillars from invading your yard than it is to wait until they’ve taken control of your yard for these reasons:

• Reduces damage to plants
• Preserves ecosystem balance
• Prevention is less time-consuming and more cost-effective
• Protects beneficial insects, as prevention methods are more eco-friendly
• Helps you avoid the stress and inconvenience that come with pest infestations

Here are some proactive measures to keep your yard caterpillar-free:

• Inspect new plants: Before introducing new plants to your yard, thoroughly inspect them for pests or eggs. Quarantine new additions if necessary.
• Practice crop rotation: If you have a vegetable garden, practice crop rotation to disrupt pest access to their favorite plants in subsequent seasons.
• Maintain a clean garden: Keep your yard clean and free of plant debris, as these insects often seek shelter in fallen leaves and branches.
• Attract natural caterpillar predators: Natural predators like parasitic wasps and flies, birds, assassin bugs, lacewings, predaceous ground beetles, and spiders eat caterpillars and help maintain the ecosystem balance in your yard. Install birdbaths and bird feeders if you want to attract birds.
• Protect vulnerable plants: Using a spray bottle, apply soapy water to these plants to create a slippery surface that will deter these pests. Mild dish soap will not harm bugs or plants, but you also can use neem oil spray that you can find on Amazon. 
• Use cardboard or tin foil to repel caterpillars: To repel caterpillars, you can place tin foil or cardboard at the base of trees and plants. Additionally, keep the ground and surrounding plants free from debris that could easily hide caterpillar eggs.
• Avoid overwatering: Excess water paired with thatch makes a super cozy home for these pests. Apply only 1 to 1.5 inches of water weekly to lawns and plants.
• Use slow-release fertilizers: Quick-release nitrogen will cause tender top growth that caterpillars love.

FAQ about getting rid of caterpillars in your yard

What scents do caterpillars hate?

Caterpillars have a strong sense of smell, and they hate strong scents like peppermint, vinegar, lavender, hot pepper, and garlic. These can be used to mask the smell of potential food sources and shelter.

Are all species of caterpillars harmful to my yard?

No, not all types of caterpillars are harmful. Some are beneficial and serve as pollinators or food for birds. Identify the species before taking action.

An example would be swallowtail caterpillars, such as the Eastern black swallowtail and the spicebush swallowtail. Often found on plants like parsley, dill, and fennel, they are important pollinators and serve as food for birds and other wildlife.

Is it safe to use natural insecticides around pets and children?

Natural insecticides like neem oil and BT are generally safe when used according to instructions. However, exercise caution and keep pets and children away from treated areas until they dry.

Preserve the beauty of your yard

Caterpillar infestations can be frustrating. But with the right approach, you can protect your plants and restore your yard’s natural beauty. Remember that a combination of methods may be necessary for severe infestations, and maintaining a vigilant eye on your plants is the first line of defense.

Take action today, and watch your yard thrive without the burden of infestations. If you’re not confident doing the task yourself, call a lawn care professional who knows how to get rid of caterpillars in your yard.

Main Photo Credit: Frank Starmer | Flickr | CC BY-SA 2.0 DEED