So, you have a cutworm problem. And you need to quickly get rid of them.
Cutworms are some destructive pests that can wipe out your plants if you don’t do anything about them.
In this comprehensive guide you’ll learn:
- How to identify cutworm damage
- Why you have cutworms in your yard (or home)
- How to naturally get rid of them
- How to protect your plants from cutworms
- And more
You’ll have everything you need to know on this one page, so feel free to bookmark it for easy reference.
And if you have any questions, leave a comment and let me know!
Sound good? Let’s clean up your cutworm problem.
Last updated: 7/2/20.
What’s a cutworm?
A cutworm is the small, larval form of a moth.
They’re quite destructive towards plants and will do the most damage after they emerge from hibernation over the colder months. This means as the temperatures rise outdoors, you’ll find more and more cutworms coming out of nowhere.
Cutworms attack plants are a serious threat to farmers and hobbyist gardeners. They attack the new roots and leaves of seedling plants and also can climb on top of mature plants to eat the leaves.
They feed at night so they can be hard to get rid of because of their ability to hide. Cutworms also multiply rapidly as adult moths lay eggs.
They’ll continue to feed on plants causing extensive damage if left unmanaged. Over time, entire fields can be left bare where damage is extensive.
During the summer months (July), the mature cutworms burrow back into the soil and create a chamber to pupate.
After a month or so, adult moths will emerge from the soil. This usually happens from August to September.
Other cutworm names
Some other common names for cutworms are glassy cutworms, Noctuidae, moth caterpillars, army cutworms, black cutworms, floodplain cutworms, dark sword-grass, ipsilon dart, or moth larvae.
Are cutworms caterpillars?
Yes. Cutworms are considered a caterpillar and there’s no difference between them.
Cutworms pupate into adult moths. The cutworm form is just the larvae of a moth. Butterflies also pupate from caterpillars, but a different type.
What do cutworms look like?
At first glance, cutworms look like grubs of beetles. If you’ve ever seen the grub form of a beetle, you may mistake a grub for a cutworm, which are completely different species.
Cutworms range in color from pink, green, and black. They’re also often found curled up when not eating or moving, so you’ll see them in a “C” shape.
They’re also very good at hiding and avoid humans and other pests, which is why they only feed at night. Cutworms are about 2” at max length and may be solid or striped. Some are also spotted in coloration.
There are a few species of cutworms that are quite common.
These can be seen and identified by the dark spots all over their bodies. They pupate into sword-grass moths, which are darker-colored moths.
Therese cutworms are very common and have a white stripe down the center of their backs.
After the cutworm has some time to eat and feed, it’ll grow into an adult moth.
At this point, there are visible, dark wings. They’re about 1.6 inches and are easily identified by the tan and black spots on their wingspan. They’re no longer a caterpillar at this point and are now considered a moth.
Cutworm life cycle
Cutworms have a simple lifecycle. The adult moths only have one generation per year.
Cutworms overwinter as eggs and hatch in April, also known as cutworm season. The caterpillars will then feed on crops during the night.
They’ll molt over the course of six times and each instar forces the cutworm to get bigger.
During the summer (May) is when they’re most visible on your plants. The larvae continue to feed until early July or late June and burrow to create a pupal chamber.
They’ll then turn into adult moths, which come out of the soil around August.
Male and female moths then mate. The female adult moths seek out loose and dry soil and lay eggs. They’ll also lay eggs on weeds and other overgrown foliage.
You can find cutworms during the nighttime hours with a flashlight, as they’re most active during the dusk and twilight hours.
They come out a night to search for food, especially after cloudy or overcast days with minimal sunlight.
Cutworms that spend their time under the plant eat the stems and roots. They can dig under the soil and find the plant root, especially for smaller plants.
They’ll chew on the root until the plant is destroyed.
Damage from cutworms is fast and swift, so you need to act quickly if you think your plant is being eaten. If they eat the root, they can disassociate it with the rest of the plant. This means the plant will wither without a root system.
Customers will spend most of their time hidden under the soil or around the roots during the winter. When summer comes around, many emerge and find their way to the tops of plants and eat the leaves.
You may find damaged plants drying up and bare soil where plants used to be. Cutworms can destroy entire field crops, so they definitely can cause some harm to your garden plants.
They tend to feed on seedling plants that have 6-8 leaves on south-facing slopes or darker areas with light and dry soil.
Cutworms must curl around the plant stem to do damage. This is why plant stakes can help stop cutworms since they make a physical barrier around your plants. We’ll cover this in detail.
What do cutworms eat?
Cutworms eat a variety of plants and fruit.
They can climb up stems, leaves, shrubs, and vines to eat plant leaves, fruits, vegetables, and flowers. buds. Some species of cutworm stay in the soil and eat the plant roots while others climb on the actual plant to eat the foliage.
Some of their favorite plants to eat are beans, corn, cabbage, lettuce, crucifers, celery, asparagus, corn, peas, peppers, potatoes, tomatoes, turfgrass, artichokes, and carrots. They also eat plant buds.
How to tell if you have cutworms
There are multiple ways you can tell. The easiest would be to dig around the root of the plant during the winter and check for cutworm activity.
You may catch them a few inches below the soil or curled around the stem.
During the summer, you can see them on stems, leaves, and buds as they feed. If you see one cutworm, you probably have more as adult moths lay many eggs, so they rapidly multiply.
Are cutworms edible?
Yes, some people eat cutworms. But this doesn’t mean you should go out and hunt them down to eat, nor does it mean that eating cutworms is safe. You should avoid eating these bugs and keep your kids and pets away from them.
What do cutworms turn into?
Cutworms are the larvae of moths. They’ll eventually pupate into an adult moth, which emerges from the soil around August to September.
What time do cutworms come out?
Cutworms are nocturnal and come out at night to eat plants. They hide during the daytime and colder months and also tend to avoid any activity when the temperature drops.
This makes it hard to see them and catch them because they’re always hiding. You’ll only see them out and active during the night after sunset
Do cutworms bite humans?
Cutworms only eat plants and don’t bite humans.
Although they don’t sting, bite, or transmit diseases to humans, they can cause extensive damage to plants. New plants are especially vulnerable to their nightly attacks. Cutworms can also climb stems, vines, trees, shrubs, and more to eat the buds, fruit, and leaves.
How to get rid of cutworms naturally
You can control the cutworm population with due diligence and patience. Since cutworms are difficult to completely eliminate, you can only reduce their numbers without seeking professional help.
However, this should still bring down the damage from them and keep your plants healthy.
Here are some ways you can get rid of cutworms and prevent them.
Remove them manually
The most nitty-gritty method and one that actually works. Use your hands.
Put on a pair of garden gloves and get a container filled with dish soap and water. Get a flashlight and go out at night to do some cutworm hunting.
Check the tops of your plants and remove them by hand and toss them into the bucket. They’re very slow and easy to catch. The soapy water will drown them and kill them. Do this every single night until you have a hard time finding more to drown.
Use coffee grounds
Just like coffee grounds, eggshells are also a natural cutworm repellent.
Crush up some fresh eggshells and sprinkle them into the dirt around your plants. They’re also an excellent source of calcium for your soil.
Make DIY plant collars
You can build collars around your plant stems to prevent cutworms from touching the base of your plants.
Use a piece of cardboard and fold it into a “tunnel” wrapped around each plant stem. This will act as a “fence” to keep the cutworms from being able to chew on the stems since they can’t chew through the cardboard (or at least have no reason to).
This should be done for new plants that you’re transplanting or for smaller plants.
Established plants should be avoided so you don’t damage them. The cardboard is basically just a barrier that shields the plant roots from cutworms being able to chew on them.
Toilet paper rolls
You can also use toilet paper tubes to accomplish the same thing.
They make awesome plant collars that can save your tender stems from being eaten. The tube is strong enough to block most cutworm activity and they can’t chew through it.
These are another excellent choice to prevent the cutworm from wrapping itself around the stem on seedling plants. Place two popsicle sticks, one on each side of the plant.
You can just shove them right in the soil, nearly touching the stem. The sticks stop them from being able to wrap and curl around the stem and cutting through the plant’s stalk. This is very effective to protect beans and peans from cutworms.
Cutworms do damage quickly to seedlings and small plants, so you need to act quickly to stop them.
You can also use bamboo skewers just like popsicle sticks. This will also help in stopping them from chewing through the stem and destroying the plant.
Place the skewers in a ring of stakes around the plant stem. Pretend you’re building a barrier or stakes to safeguard the plant.
Just like bamboo skewers, you can also use break toothpicks in half and stake them in a ring around the plant stem. This will stop them from chewing through to the plant stalk and thus protecting the plant.
You can also sprinkle cornmeal on the soil right around the plant’s stalk. Cutworms tend to avoid cornmeal as it’s a natural pesticide to them. If they eat it, they’ll die. So you can use this as a safe and natural cutworm killer.
Diatomaceous earth is a natural substance that can dehydrate and kill cutworms.
You can sprinkle a ring of DE around the plant stem. This forces any worm to crawl over the ring of DE in order to climb on the plant, which ensures that they’ll dehydrate over time with enough exposure.
Although DE is natural and safe, you should still wear gloves and keep pets and kids away from it. The DE will kill the cutworm over time, but usually, after some damage has already been done to the plant.
You should combine DE with another approach, such as toothpicks or stakes. DE helps for big plants, but for seedlings that have yet to mature, you’ll need a barrier or ring around the stalk.
Change your mulch
Some customers have been reported to be repelled by oak leaf mulch.
You can switch your mulch entirely to something else, or you can just get a bunch of oak leaves and make mulch out of them. Apply this mulch around your plants to naturally repel cutworms.
There are many bugs and animals out there that eat cutworms.
You can try to get some of them into your yard to eat them up. This way, you have “passive” pest control as you let nature take care of nature.
Some of the most common bugs that eat cutworms are fireflies. You can try to attract them into your garden, but of course, you’ll want to make sure that they’re native to your state first. Not all areas have fireflies.
You can check out this resource to see how you can get more of them into your yard.
Here are some other bugs that eat cutworms:
- Parasitic wasps
- Soldier beetles
- Stink bugs
- Tachinid flies
- Ground beetles
- Rove beetles
See what you have in your area and get more of it to your yard. Using bugs to eat cutworms is like having an army that’s working 24/7 for free.
Tansy also has been reported as a cutworm repellent. You can plant tansy around your most infected plants to help keep the cutworms away.
Bt stands for Bacillus thuringiensis, which is a natural microbe bacterium that live in the soil. They have a parasitic relationship with most pests and will help disturb their life cycle and stop them.
Cutworms are no exception. You can buy Bt and apply it as directed to help break the cycle. Bt also is effective against other pests like budworms.
You can buy Bt by the container at online retailers or specialty shops. Use as directed.
What animal eats cutworms?
Some animals such as bats and birds both help eat cutworms.
Bats actually eat millions of caterpillars and worms over the course of a year. Since bats feed at night, that’s when cutworms are out and about.
Thus, bats definitely can help with cutworm control. You can attract more bats to your yard using a bat box.
Birds eat caterpillars and cutworms are no exception. Consider making your yard more bird-friendly by doing the following:
- Add bird bats
- Add bird feeders
- Cultivate your soil to expose bugs for birds to eat
- Plant some plants that birds eat
- Restrain pets
- Use birdhouses
How to prevent cutworms
After you’ve brought down the current pest population, you can look into preventing them in the future.
Here are some tips you can practice to help stop future infestations of these annoying bugs.
You’ll want to keep your mulch and soil cultivated at all times. This means mulching, seeding, and fertilizing constantly.
Don’t let your soil go stagnant, as this introduces more pests and hiding places for not just cutworms. Turning over your soil constantly brings the cutworms to the surface which exposes them to predators and also disturbs them.
Prune your plants
Adult moths choose grassy and overgrown foliage to lay their eggs. If you’re not cultivating and upkeeping your plants, you’ll have a bunch of overgrown plants that are perfect targets for them to deposit eggs.
This just leads to more and more cutworms next season. You should also keep your lawn mowed and plowed.
Kill cutworms before you transplant
Cutworms emerge from the soil after the last frost. You can starve them by waiting to transplant your new plants by a month or so.
During this time, you can dig up the soil and also be on the hunt for any cutworms that emerge. Get rid of them. Then transplant your new plants.
This also allows you a safety net before you transplant if you need to do major garden work like set up plant collars or mulching.
Will Epsom salts kill cutworms?
Epsom salt may help deter cutworms.
You can sprinkle a ring of Epsom salt around the base of the plant. This way, they have to crawl over the ring of salt to reach the plant.
Set up barriers and repellents
For new seedling plants, always use a ring of DE around the stalk. This way, they have to cross it to eat the plant. This will ensure that the cutworm will be killed over time. Of course, you’ll want to use this with another method like toothpick stakes or popsicle stakes to stop them from curling around the plant.
Remember that once the cutworm curls around the stem, then the pest starts chewing through the stalk. If you can stop them from wrapping around the stalk, then no damage can be done.
Cutworms in the house
Sometimes cutworms may find their way into your home. This often happens when you bring outdoor plants into your home, or during transplanting processes.
Cutworms aren’t naturally attracted to enter human homes as they tend to avoid any contact. That’s why they’re always hiding during the day and only come out at night. If you have cutworms in your home, you should first ensure that it’s actually a cutworm.
There are many other similar caterpillars that look the same.
After that, you’ll want to see how the pest got into your home, assuming that it is a cutworm.
- Did you leave a door open or a window?
- How many are there?
- Did you move plants or buy new plants recently? Or do any soil changes?
Sometimes cutworms are hiding under plant soil from potted plants that you may have bought a long time ago and don’t come out until the temperatures pick up. Whether this is because summer is approaching or you have the heater on, you may see cutworms spawn out of nowhere when in reality they’re hiding under the soil for months.
Remember that cutworms don’t come into homes by nature. Usually, some vector brought them into your home by force.
Will Sevin dust kill cutworms?
These creatures are hard to kill because they’re so good at hiding. Sevin dust has been shown to be effective against cutworms because they’ll come into contact with the dust as they’re foraging for food.
However, you should always avoid using synthetic pesticides when possible, as they contain harmful chemicals to humans, pets, and the environment.
Don’t use them when you don’t have any. Use them as a last resort. Or if you must use a chemical, consider buying all-natural or organic pesticides.
How do you kill worms in plant soil?
Cutworms in the soil are harder to kill because they’re burrowed and hidden.
Typically, cutworms will stay in the soil during the winter until early spring when they come out of the soil to climb plants.
During the colder months, they’ll stay under the soil and feast on the plant roots. This can be damaging to new plants with sensitive and tender root systems. To kill them that are hiding in the soil, you’ll want to mulch the soil to disturb them and manually remove them.
You can also sprinkle diatomaceous earth around the soil, but try to avoid having the DE touch the roots. Just mulch the DE into the soil around it to form a barrier. These two methods will help you eliminate some of the cutworms under the soil.
Also, consider using some plant collars or toilet paper rolls to wrap around the plant stems. This can act as a protective barrier around the sensitive parts of the plant.
If the cutworms are persistent, you can try removing all the soil and placing all of it on a baking sheet. Heat it in the oven at 200F for 30 minutes. This will kill any pests and cutworms hiding in the soil.
Baking the soil sterilizes it from pests.
Note that this should only be used if you have no other options and you don’t want to replace the soil. You could swap out the old soil for new soil, but you need to make sure no pests are carried over when you replace the soil.
How do you treat the lawn for cutworms?
Cutworms in the lawn can be difficult to treat.
You’ll want to keep your lawn mowed and cultivated at all times to prevent overgrowth. Letting weeds and grass do their own thing will eventually lead to an unkempt lawn, which attracts many pests other than just cutworms.
Start by cleaning up the lawn by mowing it, trimming weeds, removing any clippings, and disposing of leaf litter.
Apply either a lawn pesticide (again, get organic or natural types) to help reduce cutworm populations. Attract natural animals that eat them, such as pigeons, little brown bats (and big bats too), and beetles.
You can also sprinkle diatomaceous earth or eggshells to help repel and eliminate cutworms. Then you’ll want to maintain the lawn afterward.
Here are some additional resources and references you may find useful:
Did you get rid of the cutworms?
That’s all I have for you.
You should now have all the knowledge you need to manage, control, and eliminate cutworms!
Use the natural techniques outlined in this guide and you should be able to reduce and control the cutworm population.
If you have questions, leave a comment and let me know.
Or if you found this page helpful, tell me!
Consider telling a friend to help me out =].
Thanks for reading.
Currently an active researcher in the pest control industry for the past 8 years- with a focus on using natural and organic methods to eliminate pest problems.
I share handy DIY pest techniques I come across here to help out others (and possibly save them from a mental breakdown).
Fight nature with nature.