Kill squash vine borers and squash bugs

No Kumbaya hippie crap, I wanna know what chemicals will kill these bastards. I’m willing to go the chemical equivalent of Elmer Fudd on them at this point.

I can’t keep any cucurbit alive for more than about 45 days because they get invaded by these two pests. I’m never sure which one ends up killing them, but anytime I lift up the dead vines, both of them are there.

Carbaryl seems to work somewhat, but That’s getting a lot harder to come by.

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Spinosad, Acetamiprid.

I gave up trying to grow zucchini because the vine borers killed them year after year before I could get any zucchini from them. I tried Seven spray, stabbing down into the stalks to kill and dig out the worms and cutting off effected stalks, but never could stop them or keep up with their invasion.

Sorry for your troubles. I lost all my zucchini and yellow squash to borers last year (tried cutting the larvae out to no avail) - AND all my cucumbers and winter squash to bacterial wilt, though I only saw a handful of cucumber beetles all season.

This year, I’m going to try growing them under low tunnels and hand-pollinate.

Good luck finding a solution that works for you!

It worked well for me but had to be applied often, especially after a rain. But I’m surprised to hear its getting hard to come by??? They still have Sevin Dust and spray at the big box stores here…at least I think so!

Sevin still available as a 5% powder. Sprinkle liberally over the entire plant.

Looks like the Sevin Dust is still carbaryl, but the sprays have changed to Zeta-Cypermethrin. Has anyone used the new formula with Zeta-Cypermethrin for cucurbit beetle? I had good luck with the Carbaryl spray and would douse the base of the plant with good results. I always noticed the beetles would go into the ground at the base of the plant.

This year I’m going to try tanglefoot around the stems of all my susceptible squash. I’ll report back later this summer whether it worked or not.

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First year in my new house I got a good harvest. 2nd year the squash bugs found us. Got a decent harvest. This year they got my plants before they could even flower. Hate them so much.

They found us the first year!

I have had a bit of luck when I diligently search the leaves for the eggs and destroy them…but you almost have to be obsessive. I found carbaryl spray in Walmart. Two different sized bottles of Sevin…one labeled Carbaryl and one the other.

For the home gardener, there is no silver bullet, but rather a series of good practices which chip away a little bit at the problem of squash vine borers and squash bugs and together can make a decent impact on reducing them.

  1. Put Carbyl / Seven powder at the base at of the plants when the plants are young and small. For more compact bush like squash plants, you will more likely need to continue this throughout the season. As running type squash such as pumpkins grow, they can take a few hits from squash vine borers later in the season.

  2. Plant powdery mildew resistant type squash if possible. This at least helps you keep the plant from getting too weakened by diseases on one front and bugs on the other front.

  3. I’ve heard read that removing old vines and throwing them in the trash at the end of the season or when they die is a good practice that helps keep the bugs or their eggs from returning back to the garden soil.

  4. Mow and Shred any dead plants at the end of the season. Then till your garden and plant a cover crop in the winter time. Re till in the spring. This can help disturb the soil and possibly kill larvae or eggs in the soil by exposing them to the elements or predation from other wildlife.

  5. Keep your plants adequately watered in the summer time with early morning waterings. A healthy plant can resist bug pressure better. Early morning watering helps to prevent leaf diseases since the leaves can dry off during the daytime.

  6. Finally, the biggest thing that can help, which the commercial guys do but may or may not be possible for many gardeners, is to rotate crop plantings each year. I’m not sure if just moving your squash from one corner of the garden to the other corner of the garden will help but a lot of big commercial guys will move pumpkins from one field to another field each year to reduce bug and disease pressure.

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BG1977, Everyone, Just my two cents worth here. I start all my squash seeds early indoors and transplant out as soon as possible. Enjoy the crop when they are bearing and after bugs do them in rip out the vines, get ready for a fall crop where they grew. Pests are just simply not worth the effort it takes to try controlling them. But this does create an ideal scenario for rotating with fall/winter vegetables. Also try new and different cultivars every year but thus far no star has emerged without pest damage. All the best to you! Randy/GA

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I gave up on zucchinis - Parthenocarpic and hand pollinating under cover produce pure results. I replaced it with Zuccetta (Tromboncino) . It can keep up with borers, it is affected, but bonces right back . It is a monster!

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I do a mix of planting and replanting, plus putting in things the borers aren’t as interested in.

I plant zuchs knowing that they’ll get hit. I actually wait until mid-June hoping that I may have missed some of the borer population. I usually get a few weeks of zuchs before the plants are totally dead… then I put in something for a Fall crop. One year I did plant some quick to mature zuchs for the replant and that worked, but I prefer variety and usually am ready for something else after all the zuchs the plants pump out in their couple of productive weeks. This year I just planted Bosa Nova, a variety that is supposed to mature very quickly (45 days?) so hopefully I’ll get a bit more production time from them before the borers get them. I’ll also wrap the stems in foil, but that seems to just delay the inevitable, at least for me.

I also plant Tatume which seems to escape most borer damage. I’ve considered Tromboncino like @galinas , but I think the vines for those are bigger than I want to deal with given my limited space. Tatume is another vining plant that can be eaten like zuchs when small (they are round and I usually harvest around baseball size, but they can go up to softball and still be good as a zuch replacement). To be honest, I like the flavor of the immature Tatume better than a lot of zuchs which I find almost too bland sometimes. You can also let them mature and use them like a winter squash, but they are a more mild flavor and not as sweet as what most people think of for winter squash so I’ve been experimenting on the best way to use them. The mature ones keep until about March for me. So it does double duty. Triple, actually, since it is pretty prolific with the blossoms and we use those stuffed and fried, yum.

Other than step number one, I’m not sure how much good it will do.

The very first year I planted squash they were already present. So I feel like they’ll find me no matter where I rotate my crop too.

They claim Butternut squash, Long Island cheese pumpkins, and Sunburst yellow squash are resistant to SVB and I’ve found this to be true. All three of these have produced very well for me even when covered with squash bugs. Eventually they kill them, but I’ve always gotten crops from these doing nothing.

I put tulle over zucchini and cucumbers to stop SVB and cucumber beetles. Other smaller insects are still able to find their way in and pollinate.

A few ideas – maybe too kumbaya for you but FWIW : )

First, it helps to know the enemy. This video is great because it shows a female adult laying the single eggs, and greater because the guy planted radishes around the squash (supposedly a deterrent – NOT!). Ignore the fact that the narrator says “HE is trying to lay eggs…”

If you are willing to search and destroy the eggs, both the borers and the squash bugs have copper colored eggs that they will lay on the back of leaves or o stems (the bugs lay egg masses; the borer lays single tiny eggs.) I watched a youtube video where the woman wrapped some duct tape in a loop around her hand backwards, touched the eggs and picked them up off the back of leaves and stems that way.

How often? This data sheet from U of Minnesota says the eggs hatch in about a week, so I’m thinking that checking for them a couple of times a week probably would keep on top of them before hatch.

Interesting idea to use a yellow bowl of water to attract and drown the adults. I’m going to try that.

I am using Bt, a biological control. Some people shoot Bt into the stems when the borers are present and try to nuke them that way (I tried on an already infested zucchini plant – seemed to help - less involved than cutting the stem open). It’s toxic for bees and butterflies, so spraying in the evening when they are less active is recommended.

Yes, apparently the tulle (wedding veil netting) tied around the stems can be very helpful, but the borers also will lay eggs other places so may not be sufficient. You can cover the plants with row cover fabric till they blossom and then uncover a couple hours a day, BUT if there are already borer larvae in the soil from past problems, this will not work. I hear it helps to turn over the soil early in the season to try to reveal the larvae that overwinter for the birds’ benefit.

If the problem is really severe and you want to try an alternative, I read about a taste test that compared winter squash types harvested prematurely as a substitute for zucchini or summer squash (I think it was Southern Exposure Seed Exchange). The winner was a winter squash named Seminole, same type of squash as butternut (C. moschata, which I agree is highly resistant to borers), apparently tastes sweeter than zucchini when harvested immature as a summer squash and people liked it best. I just grew out some Seminole seeds and am trying it for the first time this year. Tatume, a Mexican vining squash, is supposedly less susceptible too. I tried it once – didn’t really love it, but am growing it out again to retry this year.

Good luck to us all combating this dreadful pest!

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Are Luffa susceptible?

Good question, Bryan. I don’t know – have not grown it.