How to Get Rid of Squash Bugs—and Keep Them out of Your Garden for Good
Protect your cucumbers, pumpkins, squash, and other gourds from squash bugs by following these simple tips for removal and prevention.
Squash bugs take root on the undersides of leaves or near the crown of the plant, where they’ll lay clusters of oval-shaped, copper-brown eggs. If you pride yourself in growing your own pumpkins, cucumbers, squash, or other types of gourds, you might be familiar with this particular pesky garden nemesis.
Their appearance, half-inch size, and even the unpleasant odor emitted when squished cause many homeowners to mistake squash bugs for stink bugs. But squash bugs are their own evil entity. The pests inject toxins into plants and suck moisture out of the leaves, causing them to wilt, blacken, dry up, and turn brittle.
If you spot squash bugs or their eggs on your zucchini or gourds, act quickly to prevent a full-blown infestation. Mature bugs can be difficult to kill, but with a bit of diligence, homeowners can protect their prized pumpkins and savory squash from damage.
Here’s how to get rid of squash bugs and keep them from harming your harvest in the future.
STEP 1: Remove squash bugs from your plants.
If you discover squash bugs in your garden, follow one or more of these three methods to get rid of them.
Scrape off the squash bug eggs.
Remember: Squash bugs lay eggs in clusters on the undersides of leaves and at the crown of the plants, so be on the lookout. If you spot a group of the small, spherical eggs, scrape them off using a butter knife and dispose of them in the trash can. Squash bug eggs hatch about every 10 days, so you need to check plants weekly for new batches. Otherwise, you may instead discover a new generation of destructive troops in your garden.
Pick and flick adult bugs.
If you find a handful of squash bugs on your plants, simply pick them off by gloved hand and flick them into a container of dish soap mixed with water. The pests will get trapped and drown, ensuring that your harvest will remain undamaged throughout the season. Repeat this process every few days until all squash bugs are eliminated.
Set a nighttime trap.
Squash bugs tend to gather on the undersides of logs or wooden boards at night, so set some bait to catch them all at once. Place a shingle or a board in the garden during the evening, and check underneath it for squash bugs in the morning. If you’ve attracted any bugs, immediately place the board or shingle onto a hard surface and step on it, smashing the bugs underneath. You’ll need to do this daily until you don’t see any more squash bugs on your plants.
STEP 2: Prevent squash bugs from returning to your garden.
After following the methods listed above for how to get rid of squash bugs, home gardeners can take several precautions to prevent their return. Keep reading for three ways to deter squash bugs from your pumpkins, squash, and other gourds (also called cucurbits).
Lay row covers over plants.
Keep the insects away from your plants by covering crops with floating row cover material. Secure the edges of the fabric with dirt, bricks, rocks, or other heavy objects. If you’re working with taller plants, lay the row covers over hoops (which are available from a grower’s supply, home improvement store, or online), set 3 to 5 feet apart.
The spun fibers of row covers let in water, air, and light, but insects like squash bugs can’t penetrate the surface. Leave the covers on for about a month, and uncover the plants when they start to blossom.
Plant resistant varieties of squash.
Some types of squash—like butternut, royal acorn, and early summer crookneck—tend to resist squash bugs. If your garden has a history of pest infestation, stick with these varieties of squash. Check with your local extension agent for help identifying the best cucurbits to grow in your area to resist squash bugs.
Make your garden inhospitable for overwintering.
Squash bugs can overwinter in many areas of your landscape, like in squash vines and mulch. As with all garden pests, prevent the squash bugs from finding shelter by making your garden inhospitable to them. Clear all squash vines at the end of the growing season, either by burning them or disposing of them in yard waste bags that are picked up by your municipality. Also, avoid putting mulch or straw around the base of your plants.
Squash Bug vs. Stink Bug: What’s the Difference?
It might smell unpleasant when you squish a squash bug, but stink bugs smell worse yet generally do only cosmetic damage to plants. The squash bug (Anasa tristis) sucks the sap out of leaves and can cause them to wilt. It is an entirely different insect from the stink bug. The stink bugs are in the Pentatomidae family and the brown ones that get confused with squash bugs are of a genus called Euschistus.
You can tell squash bugs from stink bugs partly by appearance; the bodies of stink bugs are wider and look more like a shield. Squash bug bodies are more rectangular until you get near the head.
Another way to determine whether you’re dealing with a squash bug vs. stink bug is where you found the bug. Suash bugs flock to squashes, pumpkins, and other cucurbits to damage plants and lay the telltale grouping of bronze-colored eggs on the underside of the plants’ leaves.
Squash bugs can obliterate a young zucchini, pumpkin, or other gourd. Knowing how to kill squash bugs can keep your small patch of crops healthy. The best way to get rid of squash bugs is to keep plants watered and healthy, take steps to prevent squash bugs, and destroy any eggs you find before they hatch.
FAQs About Squash Bug Control
Sometimes, weather plays a role in just how well they thrive from one year to another. And once you get squash bugs, you are likely to see them again the next year. Read on for some answers to common questions about squash bug control.
Q: What will kill squash bugs?
The best and most eco-friendly way to kill squash bugs is by hand (or foot). Drop them immediately into a jar or similar container filled with soapy water. They cannot escape and will drown. You can scrape squash bug eggs from the underside of leaves and dispose of them or drop them into the same soapy water. If you find a group of the bugs on the bottom of a board or similar object, step on it hard.
Severe infestations might require a garden insecticide. Look for one with permethrin as an active ingredient. Treat early in the growing season and avoid spraying the flowers with insecticides; this can kill pollinators.
Q: Will vinegar kill squash bugs?
There is no evidence that vinegar will kill squash bugs. Picking them off by hand and destroying them is the most eco-friendly method.
Q: Will Dawn dish soap kill squash bugs?
Although there are reports of spraying dish soap on squash bugs to suffocate them, dish soap can damage your plants. The best use of the soap for squash bug control is to mix it with water as a solution to drown the squash bugs you pick off plants.
Insecticidal soaps designed for use in the garden are a safer choice for plants. Still, spraying the bugs with insecticidal soap only reduces new egg production, and likely will not kill adult squash bugs.
Q: Does neem oil kill squash bugs?
Neem oil can slow down squash bug reproduction by reducing how many eggs the adults can lay without harming beneficial insects. They won’t kill adults, however. Be sure to spray the undersides of leaves when using neem oil or insecticidal soap to control squash bug eggs.