6 Things To Do If You Have Caterpillars In Your Garden

Caterpillars are a common pest in your garden that can cause considerable damage to your plants. If you find caterpillars feeding in your garden, you’ll want to act quickly to get the problem under control!

The best way to get rid of caterpillars in your garden is to follow these steps:

1. Grab some gardening gloves
2. Fill a bucket with soapy water
3. Remove the caterpillars by placing them in the water
4. Check nearby areas for other caterpillars
5. Check for caterpillar eggs
6. Prevent future infestations

These critters can destroy plants but we’ve got all the info you need in this article to get rid of caterpillars and keep them from coming back. We’ll even tell you what type of damage certain caterpillars can cause so you can keep an eye out for them. 

How Did Caterpillars Even Get Into Your Garden?

Butterflies and moths are beautiful creatures, but they could be leaving behind some unwanted pests in your garden. Caterpillars are the immature form of adult butterflies and moths.

While the adults don’t really do any damage to plants, their offspring certainly will. 

Most caterpillars prefer certain plants and their parents know this. Butterflies and moths will typically lay their eggs on plants they know their babies will eat. That way, when the caterpillar hatches, it can start eating right away.

Some caterpillars can also feed on certain weeds growing near your garden. They may be waiting nearby feeding on the weeds and then move over into your newly planted veggies. 

Most Common Types Of Garden Caterpillar Pests

There are more than 14,000 caterpillar species in North America. However, you’re only going to encounter less than 1% of these in your garden!

Of the caterpillars you’ll find feeding on your veggies, the damage they do depends on what type of caterpillar you’re dealing with. 

Here is a table with some of the most common caterpillar types you’ll encounter and what kind of damage they’ll do.

Many of these harmful caterpillars will have multiple generations each year, so keep an eye out for them in your garden all season.

Catching an infestation early can make getting rid of them more manageable and reduce the overall damage they do to your plants. 

Curious about why these caterpillars chose to live in your yard? Here are things that attract caterpillars and what to do about it.

6 Things To Do If You Find Caterpillars In Your Garden

If you find you have caterpillars feeding on your garden plants, don’t fret! There are 6 simple steps you can take to get rid of caterpillars and keep your plants from being eaten. 

1. Grab Some Gardening Gloves

Whether you’re feeling squeamish about touching a caterpillar or not, we recommend you always wear protective gardening gloves when handling caterpillars or any insect.

Even if an insect isn’t venomous, or typically doesn’t bite, you never know how it will react when you reach down and grab them. 

2. Fill a bucket with soapy water

Grab yourself a bucket, or a plastic tub, and fill it with soapy water.

The soap helps to break the surface tension of the water causing insects to sink rather than float on the surface.

Dish soap is more concentrated than hand soap and tends to work best. 

3. Remove The Caterpillars

Caterpillars have 6 true legs with small claws at the front of their body and 10 prolegs on the back end.

As you remove them from your plants, use some caution so you don’t cause any damage to your plants if the caterpillar tries to hold on tight.

Most caterpillars will actually “play dead” and just fall from the plant when they’re disturbed. 

If you’re still a little squeamish about touching caterpillars with gloves, you can use a pair of tweezers to gently remove them.

Once you remove the caterpillar from your plant, you can put it into your bucket of soapy water where it will meet its demise. 

4. Check for More Caterpillars!

Most butterflies and moths lay eggs in clusters. That means if you have one caterpillar in your garden, there are likely more.

This may not always be the case, since some eggs will not hatch for various reasons, but more often than not there is more than one caterpillar at a time in your garden. 

When caterpillars first hatch, they are only a millimeter or two in length, so inspect your plants carefully. You should also try to check your plants twice per week to catch a caterpillar infestation quickly.

Make sure you check underneath leaves or veggies that might be growing. Also, check around the edges of raised beds and on the surface of your soil for any caterpillars that may be crawling around in those areas looking for their next plant victim.

5. Check for eggs

Some butterflies and moths will lay several batches of eggs in different places rather than laying them all at once. You’ll want to check the undersides of leaves on your plants for any unhatched batches of eggs. 

The eggs can be a variety of colors but are often laid in clusters of up to 100 eggs. Most eggs will be no bigger than one millimeter in size and round in shape. 

If you find eggs, you can simply wipe them off gently with a wet paper towel and destroy them. You can also prune off affected leaves and dispose of the cuttings. 

6. Prevent Future Caterpillar infestations

The best way to manage pests that harm your plants is to prevent them from ever getting a foothold in your garden.

There are many ways to prevent caterpillars. Some methods will work for all types of caterpillars while others are tailored to prevent specific caterpillars. 

In the next section, we will give you all of the details on various methods you can use to prevent caterpillars from taking up residence in your garden. You can choose the method that works best for your situation and the caterpillar pests you’re dealing with. 

9 Ways Prevent Future Caterpillar Infestations In Your Garden

Now that we know just how to get rid of garden caterpillars, let’s take a look at some of the best ways to keep them from coming back in the future!

1. Till Your Soil In Spring Or Fall

Many caterpillars actually overwinter as pupae in the soil surrounding the plants they were feeding on. They will emerge as adult butterflies and moths as soon as temperatures are high enough for their survival. And, since they’re already in your garden, the adults will likely mate and lay eggs in your garden, restarting problems you had the previous year with caterpillars. 

You should focus on tilling your garden to get rid of overwintering pupae.

By tilling the soil in spring or fall, before planting anything new, you will destroy many of these overwintering pupae. This can significantly reduce pest populations at the beginning of the growing season and give you a head start to having a happy, healthy gardening season.

Take a look at our article to learn more about caterpillars in winter and if they hibernate or stay active!

2. Remove Weeds From Your Yard

Many caterpillars found in your garden can also feed on certain weeds. If you have weeds around your garden or yard, they could be harboring caterpillars which can then move into your garden! 

One example of a caterpillar that will feed on weeds in the absence of vegetables is the tomato hornworm. They can feed on weeds like horsenettle and nightshade.

By removing any weeds in the area around your garden, you will be eliminating any alternate food sources pesky caterpillars may be feeding on. Most of these caterpillars prefer the plants in your garden and will likely end up there!

3. Install Collars To Prevent Cutworms

Cutworms can be one of the most devastating garden caterpillar pests. They typically chew younger plants around the base, just above the soil line, resulting in the plant being cut off at the base. The majority of plants are unable to recover from cutworm damage.

It doesn’t take long for a cutworm to cut down your plants; damage will generally happen overnight. This doesn’t give you time to notice you have cutworms in your garden until you walk out in the morning to find plants laying on the ground.

Prevention is essential to avoid the issues these caterpillars can cause in your garden. 

Luckily, it doesn’t take a whole lot to prevent cutworm damage in your garden. Collars are the best prevention method. A collar is basically a barrier you install around the base of your plants to keep cutworms from being able to access them.

Place a piece of cardboard (a paper towel roll works great!) in the soil approximately 2 inches away from the base of the plant. You want to make sure that the cardboard is pushed down into the soil 3 to 4 inches and rises 5 to 6 inches out of the soil. This should prevent any cutworms from accessing and feeding on the base of your plants. 

Alternatively, you can also use aluminum foil or plastic to create collars. These materials may be a little more difficult to work with than cardboard during installation, but they will hold up against water for longer than cardboard. Cardboard collars may need to be replaced from time to time.

4. Put Up Some Netting!

Putting up netting to make a tent around your plants can completely exclude caterpillars from feeding on your plants. Adults won’t be able to access them to lay their eggs.

However, netting doesn’t work for every situation. 

Netting won’t work well for plants like tomatoes that are constantly putting out new flowers which need to be pollinated to produce fruits.

Yes, netting will exclude butterflies and moths but will also exclude pollinators like bees from getting to your plants to pollinate them. 

Plants like leafy greens, broccoli, root vegetables, cauliflower, peas, beans, onions, and leeks, do not require insect pollination. These are great plants to put netting around not just to keep caterpillars out but other pest insects. 

An added benefit to netting is that it will also keep birds from eating your vegetables as they mature!

To use netting, we recommend that you don’t just drape it over your plants, but provide it with some support stakes to keep it from touching the plants.

If the netting is directly on the plants, it could cause damage to the plants, especially on windy days. The wind will make the netting move around on the plants and could result in stem or leaf damage from the rubbing action. 

If you’re thinking about adding netting to protect your garden from caterpillars, we recommend this Garden Mesh Netting Kit. It’s available in three different sizes and the mesh hole size still allows for watering without removing the netting. It also includes the hoop poles and clips needed to secure the netting and keep it from resting on top of your plants! 

6. Use Bacillus Thuringiensis (Bt)

Bacillus thuringiensis (Bt) is a naturally occurring bacterium you can find in soil which can control caterpillars in your garden.

The University of Florida states that the bacterium has to be ingested by caterpillars, where it will then release toxins, to work. The toxins cause the caterpillar to stop eating, ultimately leading to the caterpillar starving. 

An added benefit to Bt versus traditional pesticides is that it won’t harm any of the beneficial insects in your garden! Bt is most effective on young caterpillars. 

You can add Bt and water to a spray bottle and spray it over your plants. When the caterpillars feed on them they will become infected. You’ll have to reapply it periodically to keep plants protected throughout the season. 

Bonide makes a great, ready-to-use Bt spray that can be used on a variety of vegetables. We love how easy it is to use and that you don’t have to measure or mix anything. It recommends respraying plants every 5 to 7 days until insects are under control. 

7. Utilize Spinosad

Spinosad is available to use and is a byproduct of naturally occurring soil bacteria. While it is a natural product, just like Bt, it is not selective like Bt and can impact insects other than caterpillars.

It can impact pollinators, like bees, if they come into contact with spinosad before it dries.

Spinosad works best on chewing insects as it is much more effective when ingested. However, there can be some effects caused to insects that contact spinosad while it is wet.  

Once ingested, spinosad impacts the nervous system of the insect. It is effective for 1 to 2 weeks after being sprayed and has to be reapplied to remain effective.

To avoid harming pollinators use the product in the evening when pollinators are less active. 

8. Utilize Residual Pesticides (as A Last Resort)

Pesticides should be used conservatively in your garden to reduce the risk of harming desired insects.

In relity for any situation, pesticides should only be used for caterpillars as a last resort. Many broad-spectrum insecticides won’t just harm caterpillars but also the insects like bees that pollinate your plants. 

There are also many parasitic wasps that will parasitize and get rid of caterpillars for you. They can be harmed by broad-spectrum insecticides.

Green lacewings and ladybugs, which feed on the eggs of moths and butterflies, can also be harmed by these insecticides.  

Use caution when using these insecticides as you may be harming good insects in your garden. Using broad-spectrum pesticides should be reserved for situations where pest caterpillar populations have become uncontrollable after using other methods. 

Broad-spectrum insecticides include products with the active ingredients pyrethrin, malathion, bifenthrin, carbaryl, and permethrin.

Make sure you use a product that is labeled for use against caterpillars. Also make sure it is labeled for use on the plants you intend to spray. 

Follow the directions for use exactly in order to get the best control. You should also make sure to wear protective gear when using insecticides. 

9. Lower Spread Pesticides

Insecticidal soaps and oils, like neem oil, are lower-risk pesticides you can use since they won’t harm beneficial insects once they have dried. These pesticides must make direct contact with insects to be effective.

While insecticidal soaps and oils work on contact, they have to be reapplied regularly to achieve full control of pest populations.

Make sure you don’t use insecticidal soaps or oils in temperatures over 90 degrees Fahrenheit or they can cause damage to plants.

We like Garden Safe Insecticidal Soap which comes ready to use in a spray bottle and is perfect if you’re looking for an organic option to control your garden pests. Remember, the product has to make contact with the insect when you spray it to be effective. 

But Wait – Caterpillars Can Actually Benefit Your Garden!

We’ve talked about why caterpillars can be bad for your garden, but there is a bright side to having these litter critters around.

Remember, caterpillars will ultimately pupate and turn into butterflies and moths! 

There is a wide range of plants, including some in your garden, that can be pollinated by butterflies and moths. To get good quality vegetables to grow, some flowers have to be pollinated by insects. 

So having caterpillars around isn’t all bad. They may turn into some of your best garden friends and are a key component to pollinating certain plants in and around your garden. 

That’s A Wrap!

Most caterpillars are good and turn into beneficial insects for your garden. However, no one wants to see their garden being quickly devoured by them. 

The easiest way to get rid of caterpillars is to pick them off plants by hand and dispose of them in soapy water.

Remember, if you find one caterpillar there are likely more in your garden so keep any eye out. Identifying which type of caterpillar you have in your garden can help you determine which plants may be affected and the best way to protect them. 

Caterpillars can be a nuisance in the garden, but with a few preventative measures, and a watchful eye, you can ensure they won’t cause problems in yours!

References

Barrett, B.A. and Kroening, M., 2003. Caterpillars in your yard and garden (2003).

Baxendale, F.P., Keith, D.L. and Kalisch, J.A., 1989. EC89-1553 Insect Management Guide for Garden Vegetables.

Day, E.R., Hansen, M.A. and Latimer, J.G., 2019. Integrated Pest Management for Vegetable Gardens.

Kersten, M.L., Schreiner, M.A. and Skidmore, A., Integrated Pest Management (IPM) for Pollinator Conservation in Home Gardens and Small Farms.

Lingren, P.D. and Green, G.L., 1984. Suppression and management of cabbage looper populations (No. 1488-2016-124451).

Volesky, N. and Murray, M., 2019. Tomato Hornworm, Tobacco Hornworm (Manduca quinquemaculata and Manduca sexta).

Wagner, D.L., 2010. Caterpillars of Eastern North America. In Caterpillars of Eastern North America. Princeton University Press.