7 Bugs And Insects That Love Eating Your Hostas
A landscape just isn’t complete without a hosta growing in dappled shade under a tree or in your landscape. These perennials are prized for their gorgeous foliage and fragrant flowers. When you wake up one morning to find holes in your hosta leaves, it’s enough to drive you crazy!
Insects and bugs that love eating your hostas include cutworms, pill bugs, grasshoppers, black vine weevils, beetles, nematodes, and aphids. Each insect will leave different damage and clues to its presence so that you can match the bug with the most effective deterrent.
Your hostas will be back to normal in no time! Read on to discover the 7 bugs and insects that love eating your hostas, and how to stop them.
Cutworms Will Eat Your Hosta Plants
Cutworms include a wide range of species, all of which feed on different parts of the plant and appear different in terms of color, shape, and size.
It can be difficult to identify cutworms by sight because they are nocturnal feeders that only come out at night or on very cloudy rainy days.
Cutworm damage happens most often in spring, but according to the University of Minnesota, it can last throughout summer as well.
If you notice any of these signs of damage, you are probably dealing with a cutworm:
- Large holes in leaves: One species of cutworm, the climbing cutworm, will wriggle up the stems of your hosta and chow down on the leaves. They will leave large, irregular holes in the leaves.
- Clipped plants just above the ground: In early spring, you may find your hosta plants clipped right above the soil. This happens when cutworms wrap their body around the stem and feed.
- Damage to roots: Some species of cutworms don’t even bother coming out of the soil and simply chew on the roots of your hosta plants.
Cutworms are especially damaging in early spring. This is when you should be most vigilant about damage to your hosta plants.
How To Stop Cutworms From Eating Your Hostas
It can be downright icky dealing with worms on your plants. But rest assured, there are ways to deter these wriggly pests from your hosta plants.
The best way to get rid of cutworms for good is to combine a few different tactics. This will help ensure that your hosta plants stay whole and healthy throughout the growing season!
- Physically remove worms: Grab a pair of gloves and rake your fingers through the soil under your hosta plant. This will expose the cutworms which you can then dispose of.
You can also pick climbing cutworms off the leaves of your hosta plants. This is best done in the early morning or late evening when cutworms are more active.
- Eliminate cutworm hiding places: Weeds, heavy mulch, and groundcover plants all provide good hiding places for cutworms. Try to minimize or eliminate these items.
- Create a barrier of dry soil: Depending on where your hosta plant is located, if you can leave the soil extremely dry a few feet away from your hosta, this will minimize cutworms. (Of course, be sure to keep the soil directly under your hosta watered).
- Create a barrier around the hosta: Besides climbing cutworms, most cutworms will not climb over obstacles. Create a small barrier in front of your hosta to deter cutworms from your plant.
A piece of wood, cardboard, plastic, or aluminum foil sticking up a few inches from the soil will be plenty good to deter cutworms. Be sure to bury the barrier a few inches below the soil as well.
Pill Bugs Occasionally Eat Hostas
Also known as roly-polies, pill bugs are not actually bugs. They’re crabs! Well, terrestrial crustaceans at least! They are also sometimes referred to incorrectly as sow bugs.
These landlubbers are often found in humid areas such as beneath weeds and plants or under mulch. Like cutworms, pill bugs also feed at night and are not usually seen during the day.
Pill bugs are far less destructive than cutworms, but they have been known to nibble on roots and leaves of hosta plants. If you suspect pill bugs are to blame, check for the below signs of pill bug damage on your hosta plant:
- Small jagged holes in leaves: pill bugs feed similar to snails and slugs by creating irregular, jagged holes in the leaves. The holes will be quite small. Check for silver slime trails to confirm if the damage is from a snail/slug (slime trail) or a pill bug (no slime trail).
- Minor damage to roots: If you notice your hosta is struggling a little to take in water or showing minor signs of drought stress, pill bugs may have damaged the roots. This much damage only comes if there is a large population.
Most damage by pill bugs is very minor to hosta plants. One pill bug cannot kill a hosta plant, but large numbers congregating together can do significant damage.
How To Stop Roly Polies From Nibbling Your Hosta Plants
If you have a large population of pill bugs, you may need to resort to some pest management tactics.
The first step is understanding where these rolly crustaceans live. Pill bugs prefer moist, humid, dark environments. According to the University of Florida, you can find them beneath the soil, hiding under weeds, or sleeping away the day under a rock or log.
To prevent pill bugs from damaging your hostas, try these strategies:
- Avoid overwatering: As we mentioned, pill bugs love moist environments. The wetter the soil under your hosta is, the more likely a pill bug will roll on over and make itself at home.
- Rake leaves: Pill bugs feed heavily on decaying plant matter known as detritus. Fallen leaves, grass clippings, and pulled weeds can all attract pill bugs, so make haste to eliminate these items from your yard.
- Space plants appropriately: Allowing good air circulation between your hosta and its neighboring plants will help keep the humidity down, making the area less attractive to pill bugs.
On a side note, studies like the one published in the Journal of Insects have shown that detritivores (animals and insects that feed on decaying matter) boost the ecosystem around them by reducing weeds, increasing nutrient cycling, and increasing the growth of surrounding plants!
If you have your hostas in plants, take a look at our guide on removing pill bugs from potted plants for more details.
Grasshoppers Will Munch On Your Hostas
Grasshoppers can become huge pests of gardens and ornamental plants when their populations swell. Populations will fluctuate but every few years they will explode.
These well-recognized pests damage mainly the leaves of hosta plants, but if populations are large, they may eat other parts of the plant.
You can expect grasshopper damage to reach its full potential in early summer. Grasshoppers prefer to feed on leafy plants like lettuce, corn, and carrots. Since hostas have large leaves, it’s little wonder that grasshoppers are drawn to these plants to feed.
Check for these signs of grasshopper damage on your hosta plant:
- Missing sections of leaves: According to the University of California, grasshoppers use chewing mouthparts to eat leaves. This leaves large sections of the leaf missing.
- The physical presence of grasshoppers: Grasshoppers are active during the day and so can be easily spotted jumping around your hosta plants.
How To Prevent Grasshoppers From Devouring Your Hostas
Grasshoppers can be incredibly difficult to control if their population is too high. It can be downright impossible during a mass migration.
However, if the grasshopper population is small or you’re determined, they can be managed.
- Provide grassy green alternatives: Grasshoppers don’t particularly target hostas. If you want them to stay away, plant some lush green grass or plants that will stop them before they get to your hosta.
- Use floating plant covers: Plant covers allow sun and water to get in, but not pests. Valibe Floating Fabric Plant Cover can be placed directly over your hosta plants to protect them from grasshoppers during the highest population migrations. After the grasshoppers leave, you can uncover your hosta plant.
Unfortunately, grasshoppers are difficult to control once they’ve settled into your yard. Pesticides can be effective for small populations, but more grasshoppers will move in after the others have been eliminated.
You can also use specific scents that grasshoppers hate to keep them away from your garden in general for another option!
Black Vine Weevils Love Eating Hostas
Unlike the other creepy crawlers on our list so far, black vine weevils will target hostas intentionally because they are one of the weevil’s favorite host plants.
Black vine weevils can harm hostas during both the larvae and adult stages, though they feed on different materials at different stages. Larvae target the roots while adults target the foliage.
Here are some tell-tale signs of black vine weevil damage to hostas:
- Damage at edges of leaves: Black vine weevils prefer to nibble at the edges of leaves as opposed to the center.
- Signs of stress: If you take good care of your hosta but it still seems water- or nutrient-stressed, black vine weevil larvae might be responsible. They will chew and girdle roots to the point where they can no longer absorb nutrients or water for the plant.
- Presence of ‘dead’ weevils under the hosta: Black vine weevils are the opossums of the insect world. If disturbed, they will play dead and fall off the leaves of the hosta.
How To Stop Black Vine Weevils From Eating Your Hostas
Since there are two stages of the black vine weevil that damage hosta plants, we’ll have to use two different target strategies: one aimed at the larvae and one aimed at adult weevils.
To get rid of black vine weevil larvae, try using nematodes. According to the United States Department of Agriculture (USDA), nematodes are worms that are beneficial to the soil and help cycle nutrients.
Not all nematodes are beneficial, but two species Steinernema carpocapsae and Heterorhabditis heliothidis feed on black vine weevil larvae. Don’t worry, you won’t ever have to pronounce those names!
NaturesGoodGuys Live Beneficial Nematodes contains both of these species and can be applied to the soil. The best time to apply is midsummer through fall when larvae are present in the soil.
For adult black vine weevils, try one of the following strategies to prevent them from chowing down on your hostas:
- Burlap traps: Place burlap around your hosta plants, especially near the base of the plant. Black vine weevils will seek shelter in the burlap during the day. Inspect the burlap once per day and dispose of the black vine weevils promptly.
- Pitfall traps: Fill a small cup-sized container half-full with soapy water. Bury the container in the ground at the base of your hosta plant so that the lip of the container is flush with the ground.
Black vine weevils will fall into the pit trap on their way to your hostas. Empty and refill the container every few days to control adult black vine weevils.
Beetles Love Eating Your Hostas
There are a LOT of beetles out there. Surely not all beetles eat hostas, right? Right! There are only two main groups of beetles that eat hostas: blister beetles and leaf beetles.
Blister beetles are a large group of beetles that contain over 2,000 different species. They are most often seen during the day but occasionally feed at night. You can expect to see blister beetles in the summer from July through August.
Leaf beetles, also known as bean leaf beetles, resemble ladybugs but are far more damaging. Leaf beetles are active before blister beetles, from May through July.
Blister beetles and leaf beetles will both eat leaves, but blister beetles will also feed on the flowers of your hosta plants.
Signs of beetle damage to your hosta plant include:
- Missing flowers: Blister beetles may feed on the flowers of your hosta plants. If there is only one beetle, the flower may look slightly chewed. If there are many beetles, the flowers may be missing entirely.
- Skeletonized leaves: Blister beetles will crawl to the very tips of the leaves and feed inward toward the stem. As they feed, all that will be left are the veins of the leaves, making them appear as skeletons on your hosta plant.
- Ragged holes in leaves: Leaf beetles prefer to eat from the underside of leaves and will create ragged holes that measure about ⅛-inch in diameter according to the University of Minnesota.
Luckily, beetles are usually not very damaging to hosta plants. They prefer crop plants like alfalfa, beans, tomatoes, potatoes, and beets.
How To Stop Beetles From Eating Your Hosta Plants
Many species of blister beetles and all leaf beetles have very conspicuous colorations which make them easy to spot on your hosta plant.
This is good news, as it will make it easier to identify what the heck is eating your hostas! Once you identify that the responsible culprits are beetles, you can try some of the strategies below to deter them from your hostas.
- Shake them off your hosta: Get a bucket or pail and shake the leaves of your hosta plant while placing the catcher beneath. Most beetles will drop from the leaves when disturbed.
- Use floating covers: Since beetles are only active for a short time, you can use a floating cover to protect your hosta until they are less active. Valibe Plant Covers Pest Protection comes in a 10 x 30-foot roll that can be cut to fit your hosta plant.
Floating covers are a great option if you have multiple pests trying to take a bite out of your hostas. Otherwise, physical removal is the best option.
Insecticides and pesticides are rarely needed for beetles on hosta plants.
Nematodes Love Eating Hostas
Wait a second, didn’t we just recommend adding nematodes to the soil to control black vine weevil larvae?
Don’t worry, there are good nematodes and there are bad nematodes. The ones you can apply to the soil are super beneficial. The ones we’re talking about here are not so beneficial and are, in fact, quite destructive to hostas and other plants.
There are many different species of destructive nematodes, with the highest activity happening in mid to late summer.
You cannot see nematodes because they are extremely small, typically less than 1mm long and look like worms. Nematodes can damage any part of the plant, with some species targeting the roots while others targeting flowers, leaves, stems, etc.
Signs of nematode damage include:
- Damage between the veins of the leaves: According to Clemson University, nematodes are so small that the veins of your hosta plant leaf act as a barrier. Look for lesions that run the length of the leaf but do not cross over any veins.
- Stunted growth: Some nematodes target the roots of hosta plants. As they feed on the roots, symptoms of stress will start to arise. Stunted growth is a clue that nematodes may be feasting on hosta roots.
- Yellow leaves: Another symptom of damage being done to hosta roots is yellowing leaves. This is due to a lack of nutrients and water because the roots are too damaged to absorb what’s necessary to feed the plant.
How To Deter Nematodes From Your Hostas
Nematodes are small enough that physically picking them off your hostas is out of the question. To get rid of these wriggly pests we’ll have to get a little creative.
- Avoid sprinklers: Nematodes can be carried from one leaf to another, or one plant to another, by a strong burst of water such as from an overhead sprinkler. Instead of sprinklers, use drip irrigation or simply water your hostas with a watering can.
- Wash garden tools: If you have hostas, a flowerbed, a garden, and potted plants, be sure to wash your garden tools between each area. If nematodes are infecting one area, they may hitch a ride on the soil sticking to your garden tools to your hosta plant.
- Keep your hosta healthy: The addition of water and nutrients to your hosta will help it recover quickly from any damage. Give your hosta plenty of deep, infrequent waterings. You can’t go wrong using Miracle-Gro’s All Purpose Plant Food.
Keeping your hosta healthy is a good idea if you’ve already noticed nematode damage. This will help your hosta bounce back and recover from any snacking nematodes.
Aphids Can Damage Your Hosta Plants
Aphids are not as small as nematodes, but they are still quite tiny. These soft-bodied insects will make themselves at home on the underside of hosta leaves.
Catching aphid infestations early is the key to saving hostas. Though aphids rarely kill mature plants, they can still do some damage and leave your plant looking less than healthy.
Be on the lookout in late spring for signs of aphid damage to your hosta:
- Yellow leaves: Aphids feed on the sap located inside hosta leaves. If you have a severe infestation, the leaves will begin to yellow as the sap is sucked out and they cannot replace the lost nutrients quickly enough.
- Stunted growth: Again, you’ll only see stunted growth with a severe aphid infestation. If you take good care of your hosta but it doesn’t seem to be performing, you may have an aphid problem.
- Black spots on leaves: Aphids produce a liquid called honeydew as they feed. This honeydew will coat the leaves of your hosta and will eventually cause sooty mold fungus to grow there.
- Leaf curl: According to the Univesity of California, a few species of aphids use a toxin to cause the leaves of their host plants to curl. This helps protect them from predators and sprinklers and garden hoses.
How To Prevent Aphids From Eating Your Hostas
Aphids rarely cause enough damage to hosta plants to warrant pesticides or insecticides. There are a few natural ways that you can get rid of aphids before they do too much damage.
- Inspect plants early: Check your hostas for aphids in late spring when their populations are expanding. They are most active when the weather is warm but not hot. As soon as you spot them, it’s time to take action!
- Hose them off: use your garden hose to spray your hosta leaves to remove any lingering aphids. Try to do this early in the morning to give your hosta time to dry out. This will prevent other pests from moving in on your hosta.
- Encourage predators: Try planting companion plants next to your hosta that will encourage natural predators of aphids. Butterfly weed, geraniums, marigolds, dandelion, sweet alyssum, and Queen Anne’s Lace all attract ladybugs, which will hunt down those pesky aphids.
You can read more about how to attract ladybugs to your yard and garden here.
As we mentioned, aphids only cause problems on hosta plants when there is a large infestation. Once the hot summer months hit, aphid populations will begin to decline.
If aphids are a large problem in your garden, take a look at our piece on the scents aphids hate for more natural repelling options.
That’s A Wrap!
It’s frustrating and annoying to see little holes or chew marks in your once-beautiful hosta plants. You may be wondering what exactly is plaguing your hostas? Well, let’s have a quick recap!
The 7 bugs and insects that LOVE eating your hostas include:
- Pill Bugs
- Black Vine Weevils
- Beetles – blister beetle, leaf beetle
The most destructive of these are probably cutworms and black vine weevils, but each pest can do significant damage when their numbers are high enough.
If you still aren’t convinced that it’s insects going after your hostas, I encourage you to check out our article on the most common animals that love eating your hostas – it’s a doozy!
Inspecting your hostas for signs of pests and making a few practical modifications will reduce the presence of insects and keep your hosta bug free!
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