Coreopsis beetles are voracious eaters and will consume and destroy aster family plants like it’s their favorite food!
These pests aren’t too common in the garden.
But when you do have an infestation, you’ll want to eradicate them quickly because they don’t waste time.
These beetles are considered a serious infestation and you should act accordingly or else your coreopsis will be left with a bunch of holes in the leaves, chewed down stems, and jagged foliage with chew marks around the edges.
In this guide, you’ll learn about:
- Why you have coreopsis beetles
- How to identify them vs. other common garden pests
- Signs of a coreopsis beetle infestations – what to look for
- Ways to protect your aster plants from beetle damage
- Natural ways to get rid of tickseed beetles
- How to get rid of them for good
- And more
You should have a solid understanding by the time you make it through this guide.
If you have any questions, you can drop a comment at the end of this page and I’ll try to help you out (as always!).
Now, let’s get those beetles off your coreopsis and into the organic compost bin!
What’s a coreopsis beetle?
The coreopsis beetle (Calligrapha californica) is a peculiar beetle with a striking design on its back.
This tiny quarter-inch pest is responsible for the destruction of tickseed plants is the bane of many gardeners- and many headaches!
It’s commonly found in gardens, nurseries, and other areas where tickseed is grown in dense groups. They leave behind skeletonized leaves in their wake.
Although their infestations aren’t common, when you do have one, it’s a PITA to deal with.
These beetles are hard-shelled, which makes them resilient to many of the common pest control methods.
They feed almost exclusively on coreopsis (AKA tickseed or tickweed).
So if you have this beetle, the only way to “completely ” get rid of it is to remove the coreopsis plants.
Of course, that’s not why you’re here. You want to save your plants and knock those beetles out.
And that’s why you’re here.
Let’s learn how to naturally control, manage and eliminate these pests with DIY remedies you can do at home. Let’s roll.
These pests have spawned a few other nomenclatures you may be family with.
These nicknames refer to the same beetle:
- Tickseed beetle
- Tickweed beetle
- Orange ladybug
- Striped ladybug
- Coreopsis leaf beetle (mistakenly)
- Calligrapha californica
- Coreopsis ladybug
Don’t get it confused with Phaedon destonis
The Phaedon destonis (coreopsis leaf beetle) is another beetle that’s found eating coreopsis.
It’s relatively new to the scene, as it’s only been in recent years that it was prevalent enough to garner enough attention from entomologists.
The difference between coreopsis beetles and Phadeon destonis is easy to tell:
- Coreopsis beetles have a black and yellow body
- Phaedon destonis has a green or purple body
- Coreopsis beetles are bright in color, while Phaedon destonis are darker in contrast
- Phaedon destonis is solid in color, while coreopsis beetles have stripes
If you think you have coreopsis leaf beetles, the method to get rid of them is similar to regular tickseed beetles.
You can use the same methods on this page to get rid of them. The same methods should work for both.
Regardless, you should act quickly because these beetles are voracious eaters and will destroy your aster plant.
Appearance – What do they look like?
C. californica is a small beetle, but still visible to the naked eye. It’s about ¼ inch in length and looks like a ladybug.
It’s commonly confused with them because of the patterning, but the colors are completely different.
They have a dark body with yellow stripes going down them running parallel to their head.
If you’ve seen a potato beetle before, coreopsis beetles look very similar to them.
They look like ladybugs, but with different patterns on the back. It’s easy to get them confused if you’re not paying attention.
But if you look closely, you’ll find them tucked inside the wedge between leaves enjoying themselves by munching on your coreopsis.
Ladybugs have spots on the back. Coreopsis beetles have stripes.
That’s the easiest way to tell the difference between core psi beetles vs. ladybugs.
Two antennae jut out of the head and six visible legs. The rear legs are powerful and large. There are three visible segments in the body.
The stripes are black and yellow or orange in alternating patterns. They go down from the head to the rear. Three black stripes with four orange stripes are common.
When are they active?
They come out when coreopsis is growing younger leaves in the growing season, which is usually around spring to summer.
Coreopsis grows in zones 4-10, so the beetles are found in the same zones with the same active pattern. When coreopsis is thriving, so are the beetles.
Depending on where you live and the strain of tickseed you’re growing, this time frame varies slightly. It’s usually between May to June when they start showing themselves on your plants.
The adults are active in the summertime and will mate then deposit their eggs in dense foliage.
If you look carefully at the base of your coreopsis (where the stem meets the soil), that’s the area that eggs are laid. The adults find a host plant to infest in the summertime and they hatch three seasons later in the spring.
Pregnant female beetles are enlarged.
They go dormant over the winter and will continue to remain there.
When the temperatures pick up again in the following spring, the eggs will incubate and hatch. Small beetle larvae will come out and feed on the coreopsis plant.
This is where the majority of the damage is done. The larvae feed on the leaves. They can also chew on the stems, which will reduce their height. You may see some coreopsis that is tall while others are short.
This could be because of pest activity. The only task for these larvae is to feed on the plant to get enough nutrients for pupation. They feed until fall.
When the summertime comes, the larvae pupate (roll themselves into a cocoon) and then will emerge as adult beetles. The overwinter produces pupae.
The adults then continue feeding on the coreopsis, further damaging your plants. The adults don’t do nearly as much damage as the larvae do.
The adults then mate and lay eggs once again. The entire cycle is quick and this is why you can have a sudden bloom of these pests on your plants.
What do they eat?
The coreopsis beetle only eats tickseed. It’s found on other plants as well, but it doesn’t infest them. It may just be passing by.
Although they may temperature feed on other plants in the same family as coreopsis (Asteraceae), it prefers to eat coreopsis when it’s available.
You may find it munching on other asters like zinnia, dahlia, or ragweed. These flowers all have flowers that look like daisies.
They like newly sprouted foliage.
Seedlings or new leaves that grow out of stems are the perfect snacks for coreopsis beetles. The leaves are tender, soft, and full of nutrients for them to munch on.
They’re also very easy to digest so it’s no wonder why they eat those young flowers.
The adults and the larvae eat tickseed. They devour coreopsis like it’s their favorite meal (pro tip: it is).
If you notice that your tickseed leaves are getting shredded, it’s very likely because of these beetles. Look for the common signs of coreopsis beetle infestation and take it from there.
These pests are known as periodic insects, meaning that they appear and destroy the plant for a short period.
But then they suddenly disappear for an extended period, with little to no activity. This can make a lot of gardeners put their guard down- thinning that the beetles left on their own.
But then again, they’re just going dormant and will be ready to eat your tickseed later on.
Where are they found?
Coreopsis beetles eat tickseed exclusively, so they’re found anywhere that tickseed is grown- whether natively or artificially cultivated.
This is usually in USDA hardiness zones 4-10.
If you cultivate your plants indoors or in a greenhouse out of their native habitat, you likely won’t ever have to deal with them, unless you bought your plants as an import from another infested state.
Where do they hide?
Coreopsis beetles don’t hide. They’re easily visible on the leaf and stems because of their striking contrast on their bodies.
The yellow/black stripes are easy to spot on green foliage, so adaptation probably didn’t work in their favor.
Regardless, this makes it easy to pick them off manually when you come across them and toss them into a bucket of soapy water.
You may see adults hanging around the base of your tickseed plant- they could be looking for a site to lay eggs.
Larvae may hang out on the undersides of the leaves to hide from predators or sunlight. If you look closely during peak season when these beetles are active (spring and summer), you can spot them easily.
Signs of tickseed beetle damage
Damage from coreopsis beetles is easy to spot. If you see any beetles, you need to do something right away before your entire tickseed becomes their next meal.
Remember that tickseed beetles are active, then inactive for a period of time. If you see them feasting on your plants then suddenly vanish, expect them to be back the next time the weather picks up again.
They don’t leave on their own until your tickseed is decimated. Don’t assume the problem is taken care of and be complacent about it. Do something!
There are some common signs of damage you should look out for:
- Random holes in your leaves
- New leaves being eaten or damaged
- Jagged or irregular edges on leaves from chewing
- Visible beetles on the tickseed plant
- Stem damage (chewed a couple inches down to the soil)
- Leaves being eaten between the veins
- Skeletonized leaves stripped of their green foliage
If you see any of these symptoms on your coreopsis, it may be due to beetle activity.
Ironically, they don’t seem to eat the flower and will ignore it. They just like to chew on the leaves and occasionally the stems.
What is eating my tickseed?
Tickseed’s large flowers and ample foliage provide a delicious meal for many different insects.
Some of the most common coreopsis pests you’ll find in the garden are:
- Coreopsis beetles (Calligrapha californica)
- Coreopsis leaf beetles (Phaedon destonis)
How to get rid of tickseed beetles
The first thing you should know- these beetles are tough to get rid of completely.
While some remedies may work to reduce their population, there hardly exists anything that’ll wipe them out completely.
If you’re dealing with the close cousin of the tickseed beetle (coreopsis leaf beetle), these are new to the world of pests and there is hardly any clear documentation on them yet.
Some organizations are asking gardeners to report infestations so they can aggregate data.
While you can help protect your coreopsis from some beetle problems, your expectations should stop there.
There are various DIY home remedies to naturally get rid of tickseed beetles.
Depending on your situation, you’ll want to start with the easiest method first and then scale up to the more “extreme” ones.
As with any homemade solution, always exercise caution and use common sense. Use proper protection, equipment, and always read the labels of products before using them- and use as directed!
You should be able to put a dent in the beetle population with these remedies. If you have any additional tips or tricks to eliminate them, post a comment and let other readers know!
Use soapy water
Using soap water will kill beetles almost instantly. Dilute a few tablespoons of dish detergent into a quart of water, then spray down any beetles you come across.
Dish soap can also be used in a bucket for manual removal. You can pick them off and throw them into it to kill them.
Test the soap solution on a small part of your copies first before applying it to the whole thing. If it’s too strong, dilute with more water or less soap. Wait 48 hours to check for plant damage.
Keep your coreopsis well pruned so it stays clean and tidy.
The leaves also block out sunlight, which attracts bugs that prefer darker conditions and shy away from light. You should already be keeping your garden clean and pruned so it’s not wild.
This will keep bugs from nestling into it. You may also be happy to know that pruning your tickseed will encourage more flowers and reduce fungal problems from poor circulation or humidity levels.
Clean up the garden
Garden insects love to infest yards that are unkempt and growing like weeds.
Spend a weekend (or two) and do a deep clean of your garden. Once you get it clean once, it’s just about maintenance afterward.
Yes, it’s annoying and takes up time. But it helps keep bugs away in general (and out of your house).
Here are some things you can do to make your yard less favorite to insects:
- Keep your plants pruned
- Remove any unnecessary plants
- Clean up leaf litter
- Never leave grass clippings behind
- Mow the lawn
Doing these tasks will take time, but they also help keep your garden tidy. A clean garden with minimal hiding places means fewer bugs in general.
Think about it: When one bug gets in and finds a plant to eat, it’ll settle down there. Then other pests that eat that first bug will come in.
Then even bigger bugs that eat both bugs will pop up. You get the point.
So if you keep it clean and eliminate hiding places by keeping your plants pruned and eliminating extra foliage, it helps overall.
Those first bugs will be less likely to infest your yard and will probably go to your neighbor’s instead.
If you don’t have the time, consider hiring a gardener to help you out.
Sticky traps can be used to help catch beetles and other bugs passively. The traps can be in the form of sticky domes or traps that are baited with a beetle attractant.
When they get in, they can’t get out.
Some are lined with other compounds that kill beetles.
You can buy some sticky tape and line the perimeter of your tickseed flower bed with it. Use stakes to make a “pen” around the plot.
Then tie the sticky tape from one stake to the other.
Any beetles that crawl around it will get stuck. Position it close to the soil surface to trap any beetles that come into contact with it.
Insecticidal soap can be purchased from hardware stores. The large majority of soaps are safe for people, pets, and wildlife, but you should check out the label to confirm.
There are organic or natural variants available. Opt for these to reduce exposure to dangerous compounds. They’ll require dilution and a manual hand sprayer to apply.
The soap will kill beetles, aphids, whiteflies, mites, caterpillars, and other bugs you may come across.
Don’t use it when temperatures are high as it coats your coreopsis and may burn it. Use as directed and read all labels. Avoid using edibles unless the soap is approved for it.
Hire a professional
When you don’t have the time for this, consider hiring a professional exterminator to get rid of the beetles.
They have access to compounds that goes beyond the reach of the general public.
Do your research on local companies and read some reviews. Opt for organic compounds when possible.
Use Bacillus thuringiensis (Bt)
This video is a good introduction to Bt:
Bt is a bacteria that’s commonly used in industrial farming. It’s a natural way to control many different types of pests using the power of nematodes.
Bacillus thuringiensis var. Tenebioronis is considered to be completely organic and safe for household pest control. All Bt requires specific dilution requirements before use. Typically, you’ll mix some Bt by the tablespoon into water.
Then you spray it on plant surfaces thoroughly and evenly. The Bt will infest the beetles during the larvae part of their lifecycle, effectively halting their development into the destructive pests they become.
Bacillus thrigeniss var. Tenebrionis is best to use when there are a ton of tiny larvae eating your plant. It stops them from becoming adults.
You can find Bt at specialty stores. Follow the label and read all warnings before use.
Use as directed. All Bt is different for every lot you buy, so be sure to follow it precisely.
What home remedy kills coreopsis beetles?
The only way for a guaranteed kill is to use soapy water. The soap traps them and will drown them.
You can make your DIY soap spray at home using regular dish detergent combined with water in a diluted ratio.
To keep it simple, add 2 tablespoons into a quart of water or so. Then spray to directly onto the beetles as you come across them.
This works a lot more effectively if you manually remove the beetles first then dunk them into a bucket of this solution. It’ll kill them instantly.
Some products on the market may help eliminate the beetle population.
The problem with them is that they’re full of synthetic compounds that aren’t good for your, your pets, and the planet.
Consider getting a natural or organic pesticide rather than a synthetic one.
Also, you need to make sure that the right pest is LISTED on the container so you know it works before you spray.
You may have to contact the company or do some research online to see if said insecticide works on carpet beetles.
Here are some additional resources you can use to help get these pests in line:
- Calligrapha californica – Oregon State University
- Coreopsis Leaf Beetle: Texas Invasive Species Institute
- A Bundle of Beetles | Field Station
Did you protect your tickseed from pests?
Hopefully, you got some use from this guide. These beetles aren’t the easiest to get rid of and there aren’t any surefire ways to do so.
But with these tips and tricks listed here, you SHOULD be able to put a dent in their numbers.
There’s no guaranteed way to get rid of them, but doing the basics like keeping your clean, using sticky traps, spraying dish soap, exclusion, and using Bacillus thuringiensis should help.
If you have any questions, feedback/suggestions for this page, or tips for other readers to share, please leave a comment below.
Or if you found it somewhat helpful for eradicating those beetles, please let me know as well!
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.