When it comes to caring for your garden, cutworms are among the nastiest and most harmful pests to encounter. They’re often mistaken for grubs, but they’re actually the caterpillar of an adult moth. The worst part of cutworms is the damage that they can cause to plants and seedlings. You may not know how to get rid of cutworms in your garden, but there are several methods to choose from, ranging from all-natural and organic to synthetic pesticides.
What Are Cutworms?
The term “cutworm” refers to the larvae stage of a few species of moths. The adult moths lay eggs on remnants of plants from spring till autumn. Depending on the species, these eggs will hatch during spring and summer or autumn. The larvae that come to life in the autumn stay dormant during winter, hidden in the soil or tucked away in a stack of wood, only to emerge during spring, ready to feast.
These nocturnal critters are particularly destructive in the garden, especially during early spring when plants are young and tender. They get their name from their habit of “cutting” off a seedling at ground level by chewing through the stem. There are several species of climbing cutworms, and while their appearances can vary, they are typically gray or brown and about an inch long.
The peak of cutworms’ destructive activities is typically early in the gardening season. As they awaken from their winter dormancy, they indulge in their preferred diet of seedlings. Although cutworms are a type of caterpillar, they are frequently misidentified as beetle grubs, like those of Japanese beetles, which themselves are a source of significant damage to gardens.
How to Identify Cutworms
Cutworms have a broad palate, feeding on numerous types of vegetables and flowering plants. Thus, your garden’s young seedlings or transplants are potentially at risk. To spot these pests, consider a twilight or night-time survey of your garden, focusing particularly on the areas around plant bases. Cutworms also favor overcast days. If you want to protect your green beans and other vegetables you need to get these pests under control.
These pests vary in color, including shades of grey, pink, green, and black, and can grow up to two inches long. Some have a plain appearance, while others are speckled or striped. Typically, you’ll find them curled up when not in motion. Cutworms are rather elusive, feeding primarily at night and hiding during the day.
One of the most prevalent types of cutworm is the black cutworm, scientifically named Agrotis ipsilon. This variety features tiny dark spots scattered across their bodies and eventually metamorphosizes into the dark sword-grass moth.
The variegated cutworm, or Peridroma saucia saucia, is another common species. These are distinguished by their mottled brown bodies and a faint white line running down their backs.
Adult cutworms transform into moths, which typically sport dark, brown, or gray wings. These adult night-flying moths can grow to about 1½ inches in length and have a wingspan of similar measure. Stay vigilant for these adult moths as the females, post-mating, are known to deposit eggs in dry soil.
Identifying Cutworm Destruction
Cutworm damage is quite distinct. Young plants and seedlings are most at risk, and you’ll often find them severed at the soil line or sometimes completely missing. Occasionally, cutworms will climb plants and chew larger holes in the leaves, buds, or stems. A sudden loss of plants overnight is a common indication of cutworm activity.
During the summertime, cutworms may venture to the peak of plants, inflicting damage there. It’s important to differentiate this type of destruction from the harm caused by slugs or cabbage worms to accurately identify and address the threat.
17 Natural Ways to Get Rid of Cutworms
Cutworms can be formidable opponents, but they’re not invincible. Let’s dive into the natural remedies I’ve discovered and perfected over the years.
1. Manual Removal
Manual removal is a direct and straightforward method to handle cutworm infestation. It involves getting your hands dirty, literally. As dusk settles, put on your gloves, grab a flashlight, and carefully check around the stem base of your plants. The cutworms will come out of their daytime hiding to feed. Pick them off the plants and the surrounding soil.
To make this task less daunting, remember that these critters can be easily spotted by their curled, “C” shaped posture when disturbed. Dispose of them by dropping them in a bucket of soapy water. The soap will ensure they don’t crawl back out and return to your garden.
2. Coffee Grounds
Who knew your morning coffee could play a dual role as a cutworm deterrent? Coffee grounds contain caffeine and other compounds that cutworms find distasteful. You can keep these pests at bay by sprinkling used coffee grounds around your plants.
Besides, using coffee grounds in your garden is beneficial for other reasons too. They enrich the soil by adding nitrogen, an essential nutrient for plant growth. Also, the dark color of the grounds absorbs heat, which can help warm the soil in cooler temperatures.
3. Beneficial Nematodes
Beneficial nematodes are microscopic, non-segmented roundworms that prey on various pests, including cutworms. They penetrate the cutworm’s body, release bacteria that kill the host, and then cutworms feed on the contents. Introducing these beneficial nematodes into your garden soil can help control the cutworm population.
To use beneficial nematodes, you simply mix them with water and apply the solution to the soil around your plants. The nematodes will do the rest, seeking out and destroying the cutworm larvae. Plus, these nematodes are safe for your plants, pets, and even beneficial insects in your garden.
Eggshells are another handy tool in your arsenal against cutworms. These pests dislike crawling over anything sharp or jagged, and the crushed shells fit the bill perfectly. Sprinkle crushed eggshells around the base of your plants to create a barrier that deters the cutworms.
Not only do eggshells help protect your plants from cutworms, but they also improve your soil quality. Eggshells are rich in calcium, an essential nutrient for plant health. As they break down, they release this calcium into the soil, enriching it and aiding your plants’ growth.
5. Cutworm Collars
Cutworm collars act as a physical barrier, preventing the cutworms from reaching the stems of your plants. These collars can be made from various materials, including cardboard, plastic cups, or aluminum foil. Just make sure they’re at least three inches tall and insert an inch into the ground to prevent cutworms from crawling underneath.
What’s great about using cutworm collars is that they provide immediate protection for your plants. It’s a good idea to put them around your seedlings as soon as they’re planted, especially if you’ve had problems with cutworms before. This simple method can save your young plants from a disastrous cutworm attack.
6. Pest-Repelling Plants
Companion planting is a time-honored technique used by gardeners to deter pests and promote healthy plant growth. Certain plants emit strong odors or compounds that cutworms find unappealing. You can naturally deter cutworms by interspersing these plants like marigolds, geraniums, and tansy in your garden.
This method not only helps in controlling cutworms but also brings diversity to your garden. Different plants attract different beneficial insects, leading to a balanced ecosystem in your garden. The additional color and fragrance can make your garden even more enjoyable.
7. Till the Soil
Tilling your garden soil in the late fall or early spring can expose overwintering cutworm larvae to the elements and hungry birds. This reduces their population and can help control the damage they inflict. Keep in mind to till the soil deep enough as cutworm larvae can burrow down and survive the winter.
In addition to controlling cutworms, tilling also helps in improving the soil structure and nutrient content. It mixes organic matter into the soil, breaks up hard soil clumps, and improves aeration and drainage.
8. Bamboo Skewers
Bamboo skewers are a simple yet efficient method to protect your plants from cutworms. Push a skewer into the ground next to your plant stems. The skewers act as a physical barrier, making it impossible for cutworms to encircle and cut through the stem.
This is a cost-effective, quick solution, especially if you have bamboo skewers left over from your last barbecue! Plus, it’s non-toxic, making it an excellent choice for organic gardens.
9. Clean Up
Keeping your garden clean and free of debris can significantly reduce the number of places cutworms can hide during the day. Regularly remove fallen leaves, rotting fruit, and other plant debris. Also, remove old stumps and stones under which cutworms may seek refuge.
A tidy garden is not just about aesthetics. It reduces the risk of pest infestation and disease, provides better air circulation, and makes monitoring and managing your plants’ health easier.
The humble toothpick can be a surprisingly effective weapon against cutworms. Sticking a toothpick into the soil next to the plant’s stem creates a barrier that prevents cutworms from cutting down your precious plants.
Toothpicks are readily available, inexpensive, and easy to use, making them an accessible solution for any gardener. Just make sure you position them close enough to the stem so that a cutworm can’t get between the pick and the stem.
Cornmeal is a common kitchen staple that can double as a cutworm control method. Sprinkle it around your plants; cutworms are attracted to it and will consume it. However, they cannot digest it, leading to their demise.
This method is non-toxic, safe for beneficial insects, and easy to implement. Also, as the cornmeal breaks down, it adds organic matter to the soil, which can help improve its structure and nutrient content.
12. Diatomaceous Earth (DE)
Diatomaceous Earth (DE) is a natural powder made from fossilized aquatic organisms called diatoms. It works against black and army cutworms because its microscopic sharp edges can cut through the cutworm’s soft body, causing them to dehydrate and die.
To use DE, lightly dust the soil around your plants and reapply after rainfall or watering. It’s a potent deterrent not only against variegated cutworms but also against other pests like slugs, beetles, and aphids. Just make sure to use food-grade DE, which is safe for humans and pets.
13. Natural Predators
Mother Nature has her own way of controlling pest populations, including cutworms. Birds, frogs, toads, and beneficial insects like ground beetles and parasitic wasps are all-natural predators of cutworms. You can employ a biological control method against cutworms by making your garden welcoming for these creatures and eat cutworms.
Providing bird feeders, a small water source for frogs, and a habitat for beneficial insects can help attract these natural predators. Moreover, this will help maintain a balanced ecosystem in your garden, reducing the likelihood of any single pest population, including cutworms, from becoming overwhelmingly large.
14. Bacillus Thuringiensis (B.t.)
Bacillus thuringiensis (B.t.) is a naturally occurring bacterium that is lethal to cutworms and other caterpillar pests but harmless to humans, pets, and beneficial insects. When cutworms ingest B.t., it disrupts their digestive system, causing them to stop eating and die.
You can find B.t. available in many garden centers and online stores. Apply it to your plants as per the instructions on the package, usually in the evening when cutworms are most active. Repeat applications may be necessary, especially after rain or watering.
15. Essentria IC-3
Essentria IC-3 is an organic insecticide composed of a mix of horticultural oils and plant extracts. It’s non-toxic to humans and pets but lethal to a wide range of pests, including cutworms. The beauty of Essentria IC-3 is that it targets the nervous system of the pests, leading to a rapid knockdown and kill.
Before using, always remember to read the instructions on the label for the correct application rate and frequency. With Essentria IC-3, you can get fast, effective cutworm control while still maintaining an organic gardening approach.
16. Epsom Salt
Epsom salt, or magnesium sulfate, can help in the fight against cutworms. Sprinkle it around the base of your plants. Like many other pests, cutworms don’t like its taste and will steer clear of treated areas.
But Epsom salt isn’t just good for pest control. It’s also beneficial for your plants. Magnesium and sulfur are key nutrients for plant health, and Epsom salt can supplement these elements in your garden soil, promoting lush, healthy growth.
Last on our list, but definitely not least, is Spinosad. It’s a natural substance made by a soil bacterium that can be toxic to insects. It affects the nervous system of insects that eat or touch it, leading to their paralysis and eventual death. It’s effective against a wide range of pests, including cutworms.
Apply Spinosad to your plants, focusing on the stems and leaves’ undersides where cutworms are likely to feed. As with any pest control product, always read and follow the label instructions for safe and effective use. Spinosad can be a powerful tool for organic gardeners with persistent cutworm problems.
Final Words: How to Get Rid of Cutworms
Your garden is a personal sanctuary, a labor of love, and the last thing you want is to have it destroyed by these nocturnal nuisances. However, with patience, perseverance, and the help of these natural methods, you can protect your garden and keep it cutworm-free.
Remember, every garden and every situation is different. What works for one might not work for another. Don’t be afraid to experiment and see what works best for your particular situation. It is important not to lose heart and keep gardening because the physical and emotional rewards are worth it.
Trust me, the satisfaction of successfully protecting your garden from pests like cutworms using natural, eco-friendly methods is a reward in itself. You are not just a gardener then; you become a guardian of the Earth, and that’s something to be proud of.
In fact, cutworms are so good at eating that they can work their way through sizeable areas with surprising speed, destroying entire plant systems. If you’re noticing plants that look healthy but have fallen over with the stems entirely chewed through, cutworms are most likely the culprit. In the summer, cutworms will gnaw their way through the tops of plants, though many gardeners can mistake the damage they cause, assuming it’s from slugs.