What purpose do gardens serve? Well, that;s an extremely general question but I'll try my best. Its the content and intention behind thoughts and actions that override the thoughts and actions themselves in most cases. The only time this may not work is if you do something harmful with loving thoughts or vice versa, although if the intentions are backed with enough energy they will still override the thought or action. If we think about this on a deeper level then we realize that we control our world because we can control our thoughts and all experience stems from this. It is for this reason that a garden can serve any purpose that we can think of, its merely a matter of what we want. This is obviously easier in theory than practice but still very possible and real. So my answer to this question is a garden serves any purpose that you can imagine.