Seal any cut canes with glue to prevent boring insects from eating the cane centers. They kill the canes as they eat them.They can damage and kill the plant. I use Elmers white glue. The brand name one works better for me than the dollar store variety. I keep a bottle in my gardening basket.
In your zone, you will have to lift and store dahlias for the winter. I put mine in rubbermaid tubs with a bit of peat moss. I throw a few mothballs in the tub to keep the rodents away .... if there were something else that worked as well, I would use it.
I am not a mb fan, but use some outside to keep the critters out of the crawl space, garage and cutters. I don't plant the MB, but my grandma used to plant MB with her tulips to keep the critters from eating them.
