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26
Sep

How to Defeat the Squash Vine Borer

by Tiffany in Gardening

How to Get Rid of the Squash Vine BorerI have been gardening for years and I have dealt with a variety of pests and bugs. I have grown pumpkins for many years and never really had a problem with anything munching on them. Then we moved to our new homestead and I started a new garden in a totally new space. Let’s just say that my first year in our new space has been a real challenge. It has left me wanting to pull out my hair.

We had slugs eating our beans and hosta. We had caterpillars eating our cabbage. We had deer eating our tomatoes. We had aphids eating our roses. We had rust disease on our apple trees. We also had squash vine borers eating our squash plants…pumpkins, zucchini, and yellow squash. It was a complete nightmare at times but I did manage to make progress on most of these fronts and next year I am armed and ready. Pests beware!

This post though talks about the infamous squash vine borer. When your squash plants start to wilt and yellow a bit many times you assume they need more water. Except more water doesn’t help. So you take a closer look and you see a sawdust frass around the vines at the base of the plant. It looks as though something is chewing them up and spitting them out. And truth be told something is. The squash vine borer is a moth that lays eggs around the stems of squash plants. Caterpillars emerge and eat into the stalk  and with enough feeding damage to the stem, the entire plant can die. The damage they can do is astounding!

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How to Get Rid of the Squash Vine Borer

You need to start with some prevention in the early spring. Most of us buy starts or transplant starts that we grow indoors. You can wrap the stems of your squash seedlings with medical gauze. It is flexible enough to grow with plants but prevents caterpillars from eating into the stems.

Spray your plants with BTK (Bacillus Thuricide). It is a beneficial bacteria that controls the larva stage (caterpillars) of certain moths. It will not harm beneficial insects. I also use it on cabbage and plants in the brassica family who are attacked by moths/caterpillars. You can also spray with Dr. Bronner’s soap. Re-spray both after rain. Wipe down the vines, stems, leaves with a damp cloth to remove bugs and eggs once or twice a week. After spraying dust them with Diatomaceous Earth and create a ring around the plants to create a barrier.

You may want to cover your squash plants right up until they flower with a row cover, a cage, or some kind of gauzy netting that will not give moths access to the plants. Once they flower you will need to remove these impediments so the pollinators can visit.

Lay out yellow bowls full of water. The borer moths are attracted to the yellow and will drown themselves. It kills off some of them and also lets you know they are in the area. Once you spot them you will want to start digging lightly in the soil looking for them in the pupil stage. Kill them on site or give them to your chickens/quail.

Prevention is going to do more than going into attack mode AFTER they have become a problem and your squash plants are dying. Arm yourselves now for next year!

Top image credit: Jim, the Photographer