Can trellising prevent Squash Vine Borer?

SVB completely obliterates any cucurbit I try to grow. Would trellising (to keep the vines off the ground, where the larvae emerge from) help at all?

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My experience was that it took them a little longer to find them, but they still destroyed my vining summer squash on a trellis. But they don’t hurt any of the moschata varieties of squash or cushaw squash so I just grow those instead. I’ve heard you can use some of the moschata winter squashes immature the same way as summer squash but I haven’t tried it yet.

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The only effective measures against squash vine borers are putting physical barriers on the plant to prevent access. a pair of nylons can be used on a small plant gradually moving it up the vine over time. Dipel is also somewhat effective if kept on the stems.

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I second the use of moschata type squashes. You still have to worry about squash bugs, but they seem to handle them ok. If you must use other species of squash, it’s probably more helpful to let them grow on the ground and throw soil over every branching point on the vine to encourage secondary rooting. I’ve had pumpkin vines soldier on admirably this way. Surgery is also helpful, cut out the borers and bury the cut section to promote healing and rooting. Most vines recover well for me, but the bush plants are almost always toast. I hate borers.

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What I don’t get, is where the hell did they come from?

The very first year I grew squash, they completely obliterated the plants about two weeks after I started picking summer squash. I am the only one on my entire street who actually has a garden. I have to wonder what the borers were living on before me.

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The adults are strong flyers and can show up from a long ways off. One of the pests that crop rotation doesn’t really help with. I hate borers.

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I had one zucchini that was amazing last summer, somehow the SVBs missed it and it just produced and produced and produced. They got the rest of my squash plants pretty quickly.

This year I am going to do nothing but butternut and Tetsukabuto and I am going to plant them fairly late.

The damage is already done by the airborne moth laying eggs directly on the plants and the larva then tunneling around. Mature larvae or their pupas end up in the winter soil; an adult moth emerges from that. So the placement of the vines does not matter. Once there is a population of larvae or pupae in the soil, even netting is not effective (if the crop is replanted in the same location).

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It works with tromboncino, but you have to pick them even before the flowers open.

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You’ll have to spray or use a row cover. I have no idea when to start in Maryland, but here in Texas I start spraying when I see the adults (Typically about late April or May. I plant the middle of April). Spray the stems and base ONLY. Make sure you gently lift the plant up so you can spray the underside of the stem. Do not spray the flowers or flowerbuds. Use carbaryl or cyperpermethrin (Liquid sevin), something that has a residue so you don’t have to spray as often. You can use BT or spinosad, but those don’t last as long on the plant. I usually do two-three applications. It lasts about 7-10 days on the stems.
Using this method I get squash. I will still get a plant that has damage, but it’s usually one or two, instead of the entire row. I’d also recommend that you turn over the soil of your squash row after the last harvest. The larvae will burrow into the ground and then come back next year, but they typically do not go far from where they feed.

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After seeing suggestions to plant moschata winter squash to prevent borers I bought one this morning. Cooked it and it had a taste to me similar to sweet potatoes with less sweetness. Good but not like I was hoping. I was looking for a summer squash taste. Do the immature ones taste different?

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I never heard of this variety before but it looks popular. When I was reading about it they said it can be used as a rootstock to graft other less borer susceptible varieties. It never occured to me to graft squash but I wonder if that would be a possible work around.

Depending on the variety, they can make good summer squash when picked immature. Waltham butternut is pretty good, as is Seminole pumpkin. Tromboncino/zucchini rampicante is an Italian moschata selected for eating as a summer squash. I’ve never grown that one personally, but I’ve heard it can take up a lot of real estate or trellis.

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Thanks

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I grew several types of summer squash last year including trombocino. I wasn’t even in the same ballpark as any of the others when it came to taste. It was edible, but bland with none of the typical squash flavor I expect. I’d personally rather get a few flavorful Englischers from a pest riddled plant than a boatload of trombocinos.

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That’s interesting and counter to what I’ve heard others say. However, you’ve grown it and I haven’t! I’m guessing it depends, like so many other things. For example, I’ve had Long Pie pumpkins grown in Maine that were fabulous and the same variety was atrociously bland when I grew it in Kansas. I also wouldn’t be surprised if there’s more than one variety of tromboncino, but they get all lumped together for us 'Muricans.

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I got my seeds from Baker Creek. There were plenty of reviews there praising it’s taste. There were several reviews that had something similar to this though: “My family/friends don’t like summer squash, but they loved this!” Taste is subjective, but I sure didn’t enjoy biting pieces of it mixed up in stir fry, plates of fried squash, or anything else it was mixed up in.

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Yeah, nothing worse than overly bland, especially when it’s supposed to be amazing!

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I have grown this one several times. It is an absolutely ridiculous plant that can produce comically giant winter squash of a particularly phallic shape. The vines will eat your whole garden if you let them.

The immature ones will work as summer squash but the vines are not completely SVB resistant. (they are probably 90% resistant for me)

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I do still grow a few zukes, but concentrate on the newer hybrids that have fewer days until fruiting so I get more zukes before the borers get them. Last year one called Bosa Nova (40 days) worked quite well that way and I’m trying another called Dunja (47 days) this year. I also plant a hill, then wait 2 weeks and plant another so I have some overlap of plants that are alive and producing. Different zuke varieties do seem to survive for different lengths of time when under SVB assault. I grew a light green one called Limelight for a few years that was a larger plant with thicker stem and seemed to keep producing for several weeks longer than others even with the bugs munching on their stems. But the flavor was very mild and I decided it just wasn’t as good, so I’ve dropped it from my list.

In terms of zuke alternatives, I’ve noted a few times before that I’ve grown Tatume (a Mexican heirloom) as an alternative and been quite happy with it both in terms of taste and survival. It is also a smaller vine compared to many, which is why I tried it and passed on the Tromboncino when I was looking for a zuke subsistitute since I don’t have a lot of space. Tatume is worth trying, but it is a round/oblong squash so not as easy to use in some zucchini applications. If you try it, harvest at baseball size for a nice tender squash. They also make a lot of blossoms once the vines get going so they work well for fried squash blossoms.

This year I’m trying Kikinda edible gourd as well (same species as bottle gourd I think, but long and thin) which is supposed to be usable like zukes. I think it is the same as Cucuzzi grown in Italy.

For winter squash I’ve tried the Maximas, etc. but found I need to focus on Moschata types to make sure the vines survive long enough to really produce. I like Honeynut and have decided to grow Tahitian Melon squash this year, which is supposed to get huge in both vine and squash. I’m also trying South Anna butternut, which is actually a butternut/Seminole hybrid. It is supposed to be a tough plant and I’m interested to give it a whirl since it has the powdery mildew resistance of the Seminole squash so it should have that going for it besides resistance to the borers.

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