I like it, but I'm also confused by it. While the general mapping is nifty, I'm confused where the train is supposed to go- is it in the cliff kind of like a subway? Also confused by the one area that has rocks in it that makes me think it should be a waterfall, but feels more like a weird section of water to me. Mind you, my visual acuity isn't great. xD
Other than that...The layout of the plants seems nice to me, well varied overall, and I like the shape of the station. Though...That's a lot of stairs with no ending. I might make one level dark to show it leads inside....Assuming it does.