Vi, Sorry to hear about your borer problem. I had that happen about 4 years ago. I got a product made by Bayer called "Bayer Advanced" It will kill them all within 24 hours. I spread it around the bed and watered it in. The active ingredient in it is Trichlorfon. Then in the spring you should uses another product, a systemic also made by Bayer. It's called Grub Control, and the active ingredient in that is imidacloprid. I didn't dig up everything and replant, as they were well established clumps. I didn't loose any, but some were set back a while. If there are products made by other companies, just make sure they have the same active ingredient. Good luck!
