Ack! It's the evil creeping bellflower, campanula rapunculoides! It doesn't have flowers yet, but it will, and don't let their pretty appearance fool you. This is a nasty perennial weed.
The garden at my current house was full of the stuff 5 years ago when I moved in, and I am still trying to get rid of it. If I were you, I'd start trying to get rid of it now. I would start by trying to dig it up, and be careful to get as much of the root system as possible because any tiny root will grow into a new plant. After you get rid of the majority of it, you will have to stay on top of it for another few years, pulling up every leaf you see until the roots finally die. I've even resorted to painting Round Up on some of the leaves with a small paintbrush if they are in an area where they are mixed in with other plants I want to keep. (That was before I put the pesticide-free signs on my lawn!)
Good luck.
I have seen this in the back alley on the walks I take my kids on each day. I had no idea! Well, now I know! My biggest issue is getting rid of the chinese lanterns in my side yard. Yes, I know some people love 'em, but not me!
Posted by: Allison | June 16, 2009 at 05:48 PM
Oh dear! I have two big bunches of this in my side yard. I was actually pretty happy when I found out it was a campanula, I usually really love them. But this sounds like a pretty aggressive plant! I guess I should stop babying them, haha!
Posted by: Jennifer | June 16, 2009 at 07:35 PM