Squash Bug Prevention & Organic Control
If a healthy squash plant suddenly wilts, turn over a few leaves and you might see a squash bug’s distinctive bronze oval eggs. Your fears about your squash plants are confirmed! What should you do now? (Spoiler: Don’t reach for a pesticide!) Although squash bugs are notorious for wreaking havoc on squash plants, squash bug prevention and organic control are possible with the right approach. I’ll teach you how.
Key Takeaways: Squash Bug Prevention and Organic Control
- Squash bug prevention & organic control starts with identifying squash bugs: adults, nymphs, and copper-colored eggs are key signs.
- Utilize organic methods like attracting natural predators, companion planting, and hand-picking to manage squash bugs effectively.
- Traps and crop rotation can prevent future squash bug infestations by reducing overwintering sites.
- Maintain healthy plants by ensuring they are well-watered and free from debris to make them more resilient.
- Implement multiple strategies in combination for the best results in squash bug prevention & organic control.
Identifying Squash Bugs in the Garden
Before you can tackle squash bugs, it’s essential to know what you’re up against. Here’s what to look for:
- Adults are about half an inch (1.2cm) long, winged, with a grayish-brown body and flat back covered in fine dark hairs. As a defense, they give off an unpleasant odor.
- Nymphs (young squash bugs) are smaller, wingless, greenish-gray, and similar in shape to adults. They often cluster together.
- Egg clusters are oval-shaped and copper-colored and usually found on the undersides of leaves.
Not sure what you’re seeing? If the insects are tiny and white and cluster on leaf undersides, this whitefly guide will help. If you’re seeing clusters of soft-bodied insects on tender growth, that’s aphids, not squash bugs. Learn what to do in How to Get Rid of Aphids. Long brown bugs with leaf-shaped hind legs are leaf-footed bugs, not aphids or beetles. Learn how to get rid of leaf-footed bugs here. And thrips are tiny, narrow insects that are likely the culprit if your leaves look scarred, silvery, or stippled. Read how to get rid of thrips in this guide.
How Do Squash Bugs Damage Plants?
Adults and nymphs use their piercing mouth parts to suck plant juices from cucurbit crops, which include summer squash, winter squash, cucumbers, gourds, and melons. Severely affected plants’ leaves and shoots turn black, die back, and fail to produce fruit.
Organic Methods to Control and Eliminate Squash Bugs
Unfortunately, squash bugs are worthy opponents and usually require multiple methods to control them. If you do nothing, squash bugs multiply rapidly and are difficult to eradicate. Combining the following practices can be effective for squash bug prevention and organic control.
Attract Natural Predators of Squash Bugs
The tachinid fly is a natural predator of squash bugs and can be helpful in squash bug prevention and organic control. Plant a wide variety of nectar and food options to encourage tachinid flies to reside in your garden. Good plant choices to attract tachinid flies include rudbeckia, chamomile, cilantro, cosmos, dill, feverfew, borage, alyssum, and oregano.1 (Click on the plant name to read articles with planting information for each crop.)
This article explains more about how to attract beneficial insects to your garden.
Unfortunately, unlike other pests, squash bugs are not easily controlled by beneficial insects alone. Once spotted in the garden, their control requires some work on our part.
Practice Companion Planting for Squash Bug Prevention and Organic Control
Attracting beneficial insects can make companion planting even more effective and reduce harmful pests. Read Planting for Pollinators: Create a Simple Insectary Border in Your Garden for ideas that work in any space. When checking for pests, also check for pollination success. Learn how to hand pollinate squash if female fruits are withering before they grow.
Plant nasturtiums among your squash plants to help with squash bug prevention and organic control. An Iowa State University study found that planting nasturtiums among summer squash significantly decreased their numbers.2 Learn how to grow nasturtiums in this blog post.
Blue Hubbard squash is especially appealing to squash bugs. Use this fact to your advantage and plant it as a trap crop.
To do this effectively, you must plant blue Hubbard squash three or four weeks before your desired varieties. Plant blue Hubbard several feet (1-2 m) away from other varieties on the outskirts of your vegetable garden.3 Click here for blue Hubbard squash seeds. Learn more about how to grow winter squash in this blog post.
Hand-pick all Stages of Squash Bugs Daily
While it may not be the most glamorous method, hand-picking is very effective. Early detection is crucial. Check your plants daily for all stages of squash bugs; if spotted, keep a bucket of soapy water near your plant. They are a little slower in the morning–that’s when I like to do my daily check. Check the plants often and dispose of the eggs, bugs, and nymphs in the soapy water—but make sure you know what you’re looking at first! Squash bug eggs are one of the most commonly confused with beneficial insect eggs. This guide to identifying beneficial insect eggs covers the differences so you know what to remove and what to leave.
Use Traps
Trapping can be an effective organic control method for squash bugs. To do this, lay out a wooden board in your garden. Squash bugs will congregate underneath them overnight. In the morning, collect and dispose of the squash bugs.
Remove Plants if Numbers Climb
If your infestation is out of control, remove and destroy affected plants to prevent the bugs from spreading. Do not add to compost. Keep that bucket of soapy water handy, and check the area around the removed plant and under the mulch. I like to use the hose to soak out any remaining stragglers.
How to Prevent Future Infestations of Squash Bugs
Rotate Your Crops to Prevent Squash Bug Infestations
Don’t plant members of the cucurbit family in the same spot year after year. Adults overwinter in garden debris and emerge to mate and lay eggs in the spring. If you grow in the same location, you make it easy for them. Rotate your crops to prevent squash bugs from building up in the soil.
Clean Up Garden Debris
To reduce overwintering sites, remove plant debris during the growing season and clean up all plant matter when the season ends. Cleaning up decaying plant matter can also help manage roly poly infestations. Learn more about how to get rid of pill bugs in this guide.
Maintain Healthy Plants
Healthy, well-watered plants are more resilient to pest damage. Keep your plants in top shape to reduce the impact of squash bugs.
Squash bugs don’t have to spell disaster for your garden. With these organic methods and preventative measures, you can keep your plants healthy and thriving. Do you have any tips or success stories? I’d love to hear them.
Sources and Further Reading About Organic Control and Prevention of Squash Bugs:
References
- Attracting Beneficial Bugs to Your Garden, A Natural Approach to Pest Control, Jessica Walliser.
- Plant Partners, Science-Based Companion Planting Strategies for the Vegetable Garden, Jessica Walliser.
- Plant Partners, Science-Based Companion Planting Strategies for the Vegetable Garden, Jessica Walliser.
Further Reading
- The Organic Gardener’s Handbook of Natural Pest and Disease Control, A Rodale Organic Gardening Book. Edited by Fern Marshall Bradley, Barbara W. Ellis, and Deborah L. Martin.
- Prevent Garden Pests Organically
- Garden Hacks: 9 Simple Pest Control Tips
- Organic Pest Control That Really Works
- How to Get Rid of Whiteflies (Even in Hot Climates)
- How to Get Rid of Leaf-Footed Bugs (Effective IPM Strategies)
- How to Get Rid of Aphids (and When to Ignore Them)
- How to Get Rid of Thrips on Roses, Citrus & More
If this post about the organic control and prevention of squash bugs was helpful, please share it.
I used sand to surround the stems this year. This is a game changer when hand checking the plant. In the past, I had mulch underneath the plant and if the bugs dropped off they quickly had a hiding place. Now when they drop it’s obvious where they are and I’m able to kill them in the sand.
Great tip! Thanks for sharing.
I have been gardening at a community garden in Las Vegas (zone 9b) for a number of years. Squash bugs were always an issue in my beds. I used many of the techniques that you cited, but it was always a challenge. Then, a local master gardener suggested that I wouldn’t have an issue with squash bugs if I waited until after Father’s Day to plant my zucchini. I was dubious, but decided to try it. To my amazement, it worked. I have been following this planting schedule for eight years and squash bugs are not a significant issue in my raised beds. Other gardeners who continue to plant earlier in the season continue to deal with squash bugs. I love your newsletter and your Perpetual Planting Calendar has become my lesson plan for year-round gardening. Thank You!!
Great tip, thank you. I’m interested to hear what differences you’ve noted for your climate vs. my calendar. People ask me quite often about if if works for Las Vegas.
@Angela Judd,
Our Spring and Fall frost dates are comparable to yours. Our monsoon season is primarily an elevation of humidity levels rather than a significant increase in rainfall. Your annual precipitation (7+ inches) is nearly twice as much as ours (4 inches). This is my first full year using your planting calendar. Thus far, everything that I have direct sown based on your calendar has germinated and matured at rates consistent with the information provided by the seed companies – lettuce, beans (bush, pole, yard long), okra, Japanese cucumber, bok choy, parsley, spinach, cilantro, sugar snap peas, Armenian cucumbers, dill, mustard, edamame. The same is true for varieties that are transplanted – tomatoes, eggplant, kohlrabi, peppers, sweet potatoes. Your calendar has worked very well for me and I plan to continue using it.
Thank you so much. I appreciate the feedback.
@Jerry Swan,
@JerrySwan Thanks for sharing regarding squash bugs and delaying cucumber planting. Based on your second reply to Angela, I’m assuming you direct sowed cucumber seeds in your garden? Also wondering if you’ve had any problems with cucumber beetles and if their reduction in numbers is similar to squash bugs.
Also, what are your typical mid-June temps when sowing cucumber seed (or transplanting)?
@Susan,
@Jerry Swan,
Susan – My comments were only about summer squash/zucchini. I did plant cucumbers this year but I have not grown them before so I don’t have first-hand knowledge of that issue. I direct sowed the cucumbers in mid-April. Typical mid-June daytime temperatures here are in the low 100’s.