I'm desperate to grow some lovely blue hubbard or kabocha squash, but the squash vine borer gets me every time. Any tips or tricks to prevent them from coming in, or to get rid of them if they haven't fully killed the plant? I read about lining the squash stem, at ground level and an inch below, with tin foil. Does that work? Thanks all. We live in NC, if it helps.
They're very common in my area, but they only slowly kill my vines. I'm usually able to get a decent harvest before the plants die by hunting the moths in my garden at dawn. I often find them sitting conspicuously on top of leaves near my squash vines first thing in the morning and I smash them at every chance. I don't know if it actually helps, but if my vines reach a decent size before the larvae are eating their insides out, I still get a decent crop. I only have a small garden though and I haven't tried the approaches you've found online.
Personally I don't have the time/attention to hunt and destroy them individually as Jake describes, though I know that can be effective. Last year we got no winter squash except butternuts due to borers.
This year I am using row cover and late planting to try to keep them off entirely. Since the borers are done laying eggs by July, I held off on planting all my cucurbits until just the past few days, and I'll keep them under row cover until we're a week into July. In my zone I should still have time to mature the crop, and hopefully I'll avoid the borers altogether. We'll see how it goes!