This is really interesting! And kind of scary, if it's something bad that could take over! The good news, I guess, is that it is right next to the front porch, where I can keep a close eye on it.
Something I just noticed, which I didn't notice yesterday, is that the leaves are hairy. I never saw the hairs when I was looking at the plant, but I can easily see them in the picture. Does that help to narrow it down?
After looking at all of the pictures, it most closely resembles Jumpseed (Polygonum virginianum) to me, except for the variegated leaves. I see no white, cream, yellow, or anything other lighter colors on the leaves. Maybe those colors develop later?
It also looks very similar to Pink Knotweed (Persicaria capitata), which Lin pointed out.
I think I can rule out Red Shank (Persicaria maculosa), which does look very similar, but the leaf shape is wrong. It sure is pretty though!
I agree that it must be a knotweed or jumpseed of some type. I'm leaning toward knotweed, but only because I found more pictures of the leaves that resembled this plant. It may be that I just haven't found pictures of jumpseed that are correct. None of them seem to be native to my area, but it could be an ornamental that the previous owner planted (that would be a stretch), but just now started to grow. Not sure if the seeds would take that long to germinate, and while they did have some plants growing here in the flower bed, none of them were mysterious, or uncommon.
Now what to do with it. I'd like to see if it will bloom, which would help with the ID, but at the same time, I'm afraid to leave it! I think curiosity has gotten the better of me, which isn't always a good thing, and I'll leave it for now, but watch it closely for any signs of it taking over the world. Maybe potting it up would be the smart thing?
Any other suggestions would be most appreciated!
