There are infinite types of gardens. I will attempt to list some as I have been prompted:

-Vegtable garden

-Herb garden

-Commercial garden

-Rock garden

-Crystal garden

-Flower garden

-Any type of food garden

-Zen garden

-Mushroom garden

-Sky garden

-Trash garden

-Mind garden

-(Insert random word here) garden

Any space where things grow naturally is a garden in my opinion so that could be any part of the planet, or universe for that matter. Anything that is started with the intent to grow can be a garden. This is why a daycare can be a child garden. To continue to list types of gardens would be arbituary in my opinion.