Are your mums being attacked by Asiatic garden beetles? These nocturnal beetles are about ⅜ inches long with a reddish-cinnamon color. Asiatic garden beetles emerge in mid to late summer to feed on the leaves and flowers of many plants, including chrysanthemums.

    Keep reading to learn how to identify these pesky beetles and protect your garden from them. 


    Identifying Asiatic Garden Beetles

    Asiatic garden beetles are a common household pest easily identified by their reddish-brown color and the fact that they feed at night. During the day, they bury themselves in soil or mulch. 

    These beetles are a type of scarab beetle related to Japanese beetles. In mid to late summer, they emerge as adults to feed on the foliage, flowers, stems, and fruits of over 300 plant species.

    Some key signs Asiatic garden beetles are attacking your plants:

    • Devoured leaves and flowers, with skeletonized vegetation left behind overnight. Most feeding damage appears in the morning.
    • Notching along the edges of leaves from the beetles’ chewing.
    • Presence of 1/3-inch long grubs in the soil, which are the larvae stage of the beetles. Grubs are C-shaped and creamy white in color.
    • Small 3/8-inch long beetles that hide in soil and mulch during the day, coming out at night. Look for beetles congregating on light-colored walls, screens, windows, and doors at night.

    Life Cycle of Asiatic Garden Beetles

    Asiatic garden beetles have a one-year life cycle. During early spring, eggs laid in the previous season hatch into grubs. Grubs feed on grass roots underground.

    Grubs pupate and transform into adult beetles that emerge in summer, usually between June and July. Beetles feed nocturnally on flowers, leaves, and stems.

    During autumn, beetles mate and lay eggs in the soil. Eggs overwinter. Adults die off with the first hard frost.

    The grubs are the most damaging stage for lawns and turf, while the adults eat the widest variety of garden plants. Controlling grubs is key to reducing summer populations of adult beetles.


    Garden Beetles
    Image Credit: Canva

    How to Get Rid of Asiatic Garden Beetles

    Like Japanese beetles and other garden beetles, Asiatic garden beetles are difficult to control once the adults have moved in for the season. 

    Here are some things I recommend trying to eliminate Japanese and other Asiatic beetles:

    Taking the time to remove already existing beetles from your yard and garden makes a world of difference. Start by handpicking adults feeding on plants at night and drop them into soapy water. Beetles will congregate on light-colored walls, screens, windows, and doors at night, where you can capture them.

    Use pheromone traps to attract and capture beetles. I recommend placing traps away from gardens so as not to attract more beetles.

    Hunt for grubs in garden beds in early spring by digging in the top few inches of soil. This step exposes grubs to natural predators like birds.

    In addition to hand-picking beetles, there are numerous biological controls you may try.

    Apply beneficial nematodes to lawns and garden beds in early spring to control grubs in soil. Nematodes kill grubs without harming plants.

    Another option is using natural predators like birds, ground beetles, ants, and centipedes to reduce grub populations when tilling and plowing garden beds.

    Lastly, apply milky spore bacteria to lawns in early spring to kill grubs. This method takes two to three years to establish but provides long-term control.

    If you have dealt with or noticed Asiatic beetles in your yard or garden, it’s time to think about the best ways to protect plants.

    I recommend covering flowers, vegetables, and small plants with floating row covers at night to create a physical barrier against beetles. You can also interplant flowers and vegetables with strongly scented herbs like mint, thyme, or sage to deter beetles.

    Always clean up fallen leaves and debris where beetles overwinter and till garden beds in the fall to disrupt eggs.

    When manual control and prevention techniques aren’t enough, consider employing chemical controls. 

    Apply insecticidal soap or neem oil to deter beetles from eating leaves and flowers. Reapply after rain. Another option is using pheromone traps to lure beetles away from plants. Place traps at the edges of the property.

    Per label directions, apply grub-killing insecticides like trichlorfon or carbaryl in early spring to reduce summer adults. Spray plants with insecticides containing pyrethrin oils in the evening when beetles are active. Reapply after rain.


    Preventing Future Infestations

    Once you’ve successfully dealt with your Asiatic beetle issue, you don’t want them to return. 

    Here are some tips to prevent Asiatic garden beetles from becoming a problem again:

    • Maintain a healthy lawn and garden beds to discourage beetle damage. Healthy plants can better withstand feeding.
    • Till up garden beds thoroughly in fall to expose eggs and grubs to predators. Compost plant debris.
    • Apply beneficial nematodes to lawns and garden soil in early spring to kill grubs before they pupate.
    • Place pheromone traps around the property’s perimeter to capture beetles and reduce numbers.
    • Inspect plants vigilantly at first signs of spring growth for early damage or grubs in the soil. Take action early.
    • Cover new transplants and seedlings with floating row covers to protect them from adult beetle feeding.
    • Plant beetle-resistant plants like Marigolds, Alliums, Asters, Lavender, Mint, and Sage.

    With persistence and a multi-pronged approach focusing on biological controls, you can reduce Asiatic garden beetle damage and avoid major infestations in the future.


    So, Is There a Foolproof Way to Control Asiatic Garden Beetles?

    Unfortunately, there is no single foolproof method for controlling Asiatic garden beetles. Their life cycle, nocturnal behavior, and wide host range make them challenging pests to manage. The most effective approach is to employ multiple strategies focused on biological control and prevention.

    Manually removing adults, applying beneficial nematodes for grub control, using row covers to protect plants, maintaining healthy soil, and disrupting their life cycle are examples of tactics you can combine to minimize beetle damage. While insecticides have a role, they should be selective and timed carefully to avoid harming pollinators and other beneficial insects.

    Protecting your garden from Asiatic beetles without resorting to harmful chemicals takes patience and persistence. If you are losing the battle, I highly suggest contacting a pest control company.


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    FAQs About Controlling Asiatic Garden Beetles

    What plants do Asiatic garden beetles attack?

    Asiatic garden beetles feed on over 300 different kinds of plants. Favorite targets include roses, grapes, beans, hops, raspberries, fruit trees, corn, and many herbaceous ornamentals like chrysanthemums, hibiscus, dahlias, and more. They typically avoid plants with strong scents like mint, lavender, or alliums.


    When are Asiatic garden beetles most active?

    The adult beetles emerge and are most active between June and September. Their peak activity is at night when they feed on plants. During the day, they hide in soil, leaf litter, or other dark places.


    How can I tell if I have Asiatic garden beetle grubs in my lawn?

    Damaged grass that is easily pulled up, patches of dead grass, and birds repeatedly digging in the same areas can indicate white grub infestation. To confirm, dig up a 1 square foot section of grass about 2 to 3 inches deep and search for plump, C-shaped grubs.


    Are Asiatic garden beetles and Japanese beetles the same?

    No, Asiatic and Japanese beetles are two different species. However, they are related, have similar behaviors, and techniques used to manage Japanese beetles will also help deter Asiatic garden beetles. The main difference is that Asiatic beetles are active at night, while Japanese beetles feed during the day.


    What is the best organic way to get rid of Asiatic garden beetles?

    Introducing beneficial nematodes to your soil is the most effective organic treatment. The nematodes kill beetle grubs but won’t harm plants or pollinators. Natural predators like ants, ground beetles, and birds also help control grubs when exposed. Floating row covers can keep adults off plants at night.



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    Jordan Tyler Quinn Farkas

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    Jordan Tyler Quinn Farkas is a globetrotting content writer hailing from the USA. With a passion for pest control, he brings a unique perspective to his writing from his early years working for one of the largest pest control companies in America. Throughout his early 20s, Jordan gained valuable experience and knowledge in the field, tackling pest infestations head-on and ensuring the well-being of countless homes.

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    Amy DeYoung

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    Amy DeYoung has a passion for educating and motivating homeowners to improve their lives through home improvement projects and preventative measures. She is a content writer and editor specializing in pest control, moving, window, and lawn/gardening content for Today’s Homeowner. Amy utilizes her own experience within the pest control and real estate industry to educate readers. She studied business, communications, and writing at Arizona State University.

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