Squash vine borer prevention and control is key to a healthy squash harvest. A lot of people wonder how to get rid of squash vine borers so knowing these options will make your gardening experience happier and more fruitful!

How to Get Rid of Squash Vine Borer – Prevention & Tips

Have you noticed your squash plant leaves are wilting and it’s not even the hottest part of the day? Finding green, yellow or orange mush piles around squash plants in your vegetable garden?

If your squash and pumpkin stems have rotten spots, you may have a squash vine borer problem. Don’t worry though. Here’s how to save your plant and your harvest.

What is a Squash Vine Borer?

The Squash Vine Borer is a translucent bodied larvae with a brownish colored head that grows up to a half inch long. Adult squash vine borer moths are actually pretty orange and black winged Seelid moths with black/grey bodies and greenish wings. 

Seelid adult moths are often mistaken for a bee or a wasp (they remind me of colorful soldier flies though) as they move like a bee.  However, these are not a friend to your garden or pantry as they will destroy and kill your harvest for years to come.

These nasty squash vine borer larvae lay their eggs around the base of your squash plants. There, they hatch and tunnel into the plant stems which weaken the plant. Eventually, they kill your squash plants. Summer squash, winter squash, zucchini – none of it is safe from this nasty foe.

Squash Vine Borer Life Cycle

After emerging from the soil, Seelid moths mate and lay flat, brown eggs on and around the base and stems of cucurbit host plants. The eggs hatch 7-10 days later. The larvae (now called the squash vine borer) eat into the squash stems, and sometimes your actual veggies.

The stems begin to hollow out. This makes mush of the plant and kill them in only four to six weeks. 

The larvae will burrow into the soil to pupate, where they will overwinter in the soil and emerge the following summer to lay even more eggs on your plants.

Welcome to the HOW TO KILL GARDEN PESTS SERIES! 

Who knew gardeners could take such pleasure in murdering annoying garden pests. If you garden, you’ll want to check out on the posts in this HOW TO KILL series. I’m adding new posts to this series each week, so subscribe to my newsletter if you want to know when they’re ready!

• How to Kill Cucumber Beetles
• How to Kill Potato Beetles
• Murdering Japanese Beetles
• How to Kill Cabbage Worms
• How to Kill Tomato Hornworms
• Controlling and Preventing Squash Bugs
• How to Get Rid of Squash Vine Borers

9 Methods for Killing & Preventing Squash Vine Borer

Companion Plants to Deter Squash Vine Borer

I always recommend planting beneficial herbs and flowers in every garden. Several companion plants can help deter squash vine borer.

• Mint and nasturtiums repel squash vine borer with their scents.  
• Beans provide nitrogen which helps feed your squash so it is strong. That makes it more likely to resist damage. 
• Planting thyme, pot marigolds, tansy, peppermint and wormwood help repel the larae borer. I like to keep multiple pots of herbs so I can swap them out as needed. Mixing up scents is always confusing to pests.

Plant Trap Crops

Hubbard squash is an excellent trap crop to grow outside of the garden in hopes of luring the Squash Vine Borer away.  It seems to prefer Hubbard above all other squash, zucchini and pumpkins. 

Hubbard squash is also an excellent trap crop for other pests too.I know folks say to plant resistant moshato type squash but I’ve seen Butternut harmed by borers as well.   

How to Get Rid of Squash Vine Borers

You can treat using Sevin or Pyrethrum.  I’m not a fan of using chemical pesticides, though, as more and more of our pollinators are struggling. These pesticides will also kill the good insects along with the bad insects. 

You can treat it if you catch it early enough by cutting the stem right off, finding the larvae and feeding it to chickens or drowning them in some soapy water. 

Depending on the damage you may want to just toss the whole plant on the fire or if you catch it early you can sometimes cut a slit and pop the larvae out and toss it in the soapy water. 

If you have to cut a stem with fruit/veg growing from it, toss the whole plant. You can still eat what has grown. Young gourds, pumpkins, and squash are the most tender and tasty after all.

Hand Pick

Diligence is the key when it comes to most garden pests. You must be out checking on your plants at the least every other day looking for eggs or signs of larvae in the stems.  

If you find any eggs, grab some duct tape, wrap it back on itself making a circle, slide it over your fingers and use it to pull the eggs off the stems then drown them in soapy water. This is my favorite way to handle them. 

Use Bt (Bacillus Thuringiensis) Spray

Bt (Bacillus Thuringiensis) Spray is helpful and is in no way toxic to mammals or bees.  It WILL kill Monarch caterpillars so be careful when spraying it.

If you have the space you can support monarchs by creating a safe space for them far away from any overspray.  Follow the directions on your container for how to use it. 

You can also syringe some up and stick it directly into any rotting spots where a larvae bored into your plants.

Delaying Planting Squash Plants

There are two thoughts when it comes to planting squash. Some people prefer to smart squash plants early so they plant out larger, stronger plants. 

Some people recommend delaying planting squash plants until later in the spring. The thought here is that if the pests emerge and there’s nothing to eat, they will move on in search of food elsewhere.

Use Row Covers as a Method of Squash Vine Borer Prevention

A floating row cover helps during the season of late spring to summer but make sure you don’t plant in the same spot two years in a row. 

You’ll also need to remove the row cover so insects can pollinate your squash plants. Learn how to cover a raised garden bed here.

Use Yellow Sticky Traps / Aluminum Foil

You can also set out a few yellow sticky traps or yellow bowls, hang some pheromone traps to catch the adult seelid moth before it can lay eggs. Wrapping the base of the plant with aluminum foil may also help.

Beneficial Nematodes

Spray beneficial nematodes in the spring and fall to help kill the grubs. Nematodes seem to be nature’s perfect answer to so many issues. I recommend them for every pest. 

Just make sure you get a variety specific to squash vine borers – the Sf nematode variety is what you need!. Bonus – they might also help with squash bugs too.

In summary 

You can coexist with Squash Vine Borer. Odds are they will always be there, but by planting a few extra plants you’ll be able to counter any issues with your plant’s health.

Do you know other methods for how to get rid of Squash Vine Borers?  Share your experience with us in the comments.