I have a scabious in a pot and there are a lot of seedlings on the surface. The leaves don't look like the main plant just now but it's an awful lot of 'foreign' seed to find its way into the pot.
What do you think?
I think they are groundsel seedlings. The seed comes in on little parachutes like dandelions.
Saying that, I just googled 'Butterfly Blue' (I think that's what it might be but I forget for sure) and the mature leaves aren't dissimilar-