I have cane borers? or as far as I can tell I do, I just got rid of black spot & now my poor rose is on the brink of death because they got down into the main part of the rose. these roses were here when we moved in & I managed to save 2 of them (3 total.) the last one is still struggling. I tried trimming the damaged parts off but I can't without getting rid of 70% of the rose including the main part attached to the roots. There are a few healthy stems left & what I am wondering is if I can cut these off the unhealthy part & use a root hormone on it? or is there another way I can save this rose? or is it hopeless & I need to just get rid of it before it gets my other roses sick (again)?
Well, the only treatment that I have ever heard of for this terrible infestation is to remove all branches and twigs below the infectiojn point and you could them paint the clip-wound with the special protective 'paint'. Just a word here: I have read several articles and a study that say that wound-dressing has no real value in preventing insects and disease from entering pruned plants. I do not know what to make of this, but I suppose if there have been studies, then one can't argue with factual results. Whatever you do, destroy the bits of the rose plant that you have removed. Get them either burnt or have the garbage folks take them far away...otherwise you run the risk of re-infection. I hope that this helps. Good luck.
There are a few species of cane bores (larvae)and all can cause severe damage. As mentioned, you keep cutting until you find the end of the borers work. Any growth above that will die off this year or next for sure. Prune back canes, to prevent other borers or eggs, use a drop of Elmers lue every now and then on the cut to prevent other lravar action. As long as the root or bud union are healthy, new growth will come along. Next spring give your roses a double dose of food to stimulate growth (recommended) and follow a good pattern of feeding and water along with your regular maintenance. I've had to cut canes almost allthe way to bub union in the past because I was to busy to pay attention when they needed it. Ron
So if I trim everything back to the bud onion & use elmers glue there is a chance I can save this rose EVEN IF the cane borers are down in the bud onion? I suspect they have been there for a long time, so the rose is pretty infested, when we first moved in we focused on the inside of the house, & not the outside so the roses were left to fend for themselves. Now we are working on the outside.