root barrier for monarda?
I have been dying to plant some bee balm/monarda in a corner of my yard that was kind of barren. Now this year, the pink bleeding heart that didn't come up so well last spring in the same corner is HUGE. I don't want to endanger it and I've heard monarda can be invasive. Last year the bleeding heart turned yellow pretty soon after blooming out, so I was hoping to put in something that would bloom later in the season to fill the hole. Would monarda be OK if I put it in a barrier (and how far down would that have to go?), or should I try something else--suggestions?