I"m zone 5a, too. I am in the NW suburbs of Chicago. That's kind of you to offer some of your Biokovo. I'll wait a little longer and see if any shows up. It had spread to quite a large area. If it doesn't come back, I may try out something new in that spot. My gardening area is limited, because most of the yard has been taken over by the dogs, and I can't garden in their part of the yard, or things get trampled!