Our back yard perennial border is infested by voles and one of the most terrible weed there is: campanula rapunculoides (vuohenkello in Finnish). I have tried to find something to survive both and these lovely rudbeckia laciniatas (syyspäivänhattu in Finnish) just might be an answer. I planted them on one side of the border and they seem to thrive. I covered the other side with old newspapers and on top of the papers I put bark in the hope of killing the campanulas. I plan to plant more rudbeckias there in next spring if I don't find other flowers that can take the competition.