This is not a garden. It is an amusement park with zoo, theme park, artificial lake, streams and whatnot. Naturally, there are many plants too, but this place is certainly not designed in the vein of garden.
Animal lovers beware: most of the animals are treated poorly (this is certainly not an exception in China), almost all of them walk on concrete and some huge animals like lions have few metres of space. So better skip it if you're sensitive in that regard.
The place is still I decent option for families, I guess.
There is a hotel on the other side of the road, not bad, but I suggest you to avoid this area as there is a lot of construction going on.
Btw, the whole Anji county is in the process of urbanization and this and few of the attractions nearby are set up to be major representatives of Chinese tourist traps. As the entrance was paid for me, I can't tell you about the admission fee, but there must be some. It's China, after all.