A couple of years ago, I tried to go without treating for borers as I was worried about the bees. Needless to say I had a bad infestation. I found a product produced by Beyer that said it would kill grubs instantly. I got some and treated my irises. It did work, but for the life of me I don't remember the active ingredient. It was differnent then what we use in the spring.
I've been selling some irises and a lady who bought some told me that she uses a 10% bleach solution in the spring, sprays it around each plant and said that she never has a problem with it borers. Any one else ever hear of that working?
