Overall, I like what you've done. I was wondering what this might look like in more of, what I would call, a Kelly green?
Entry # 2 is my favorite of yours. I like how the name is to the right of the image. That leaves room for a tagline beneath the name. Conseqently, I'm ruling out Entry #4.
A concern I have, is that perhaps the leaves on top of the "B", may be hard to identify upon a quick glance. Is there a way to have a stronger visual representing something like a tree or growth?
Good job, however.