How do I turn part of my backyard into a flowered-meadow (and, hopefully, a small Zen garden)?

Growing up, my yard always looked atrocious. We never treated it, trimmed it or anything except mowing it about once a week. There’s a particularly difficult to reach portion of backyard that is horrendous to tend to, so I’d like to turn it into a meadow with flowers that spread quickly and viciously prevent other things from growing, but still staying rather small. I want it to be accessible, though, so I’d like to include a small clearing to accomodate a hammock. Part of it, I’d like to be a Zen garden, as well. I know next to nothing as to how to do this, so which types of plants would you recommend? Tips on maintaining a clearing? Tips on the Zen garden?

Also, this portion of land is in the shade as a result of several trees, so flowers that grow with limited to sufficient light would be ideal, please.