It's a Jungle Out There

The first thing that caught my eye was the sheer exuberance of the garden--every inch is planted up with some wonderful thing that somehow makes way for the next plant until everything just dances with energy and life. But wait, there's more! The roof is strewn with weathered stuffed animals that made me smile, and maybe wonder just a little bit. And it gets better! Can you find the reason for that structure?