SQUASH VINE BORERS - HOW TO PREVENT?

[lazy gardener]

IIRC, from past reading, it is not too late if the borers have already entered. Granted, better to be proactive and kill the suckers before it even gets to that point. You spray your plants before any eggs are laid. Check with your extension office regarding the recommended start date. I think you have to spray after every rain and heavy dew. BT infects the newly hatched larvae and kills them immediately. If you are able to ID any plants that have been bored, you can then inject BT into the stem. I may be wrong here. Some one will have to check to see if I have correct info stored in the cranial data bank.

BT can also be used for corn ear worms, cabbage moths, and colorado potato beetles. I don't know if there is a different strain of BT for each of these pests. I have not used it in a very long time b/c I find it to be too expensive for the tiny bit of use I would get from it.

 

[drewskimac]

If they are already bored into the stem, it probably is too late. So to prevent, just keep reapplying the bt especially after rain. I don't have any of it left this year so will see if Home Depot has more in stock. I like the powder better than the liquid. It also works really well for cabbage worms.

By apply it, how do you mean? Do I mix it in a sprayer and spray it all over the vines, or sprinkle it around the base? I saw several youtube videos that demonstrated using a marinade syringe to inject the solution into the vine above where the borer entered, but I haven't seen any demonstrations for prevention. Do you use like DE for prevention? Thanks for all of your help!

 

[ewerbos]

I have this problem, and have yet to solve it! My local ag extension office (University of Maryland) recommends using the tin foil collars or spinosad or pyrethrum to prevent egg laying, but recommends BT for after they have penetrated. I'm thinking I'll try the tin foil first, but I ordered spinosad and BT also (I might apply the spinosad preventatively anyway if I chicken out).