Housing snakes in natural vivariums?

[Nafun]

My snakes are currently all in normal reptile enclosures, however I'm getting a garter this summer (hatch damn you!) and when he gets older I would like to make a natural vivarium for him.
I live in ohio where the specific subspecies of garter I'm getting is from (I know, because I had to get a permit to keep him), I grew up seeing them in the backyard and I got my first taste of herpetology when I rescued a garter that my mom was desperate to chop up with a shovel. I have read repeatedly that things like rocks, soil, and sand make terrible substrates, but can I make a vivarium with normal, natural plant life native to the area (grass, dandelions, duck weed, etc) and keep him in it?

I know that parasites are a risk, but I think I can avoid this by starting the vivarium sans-snake, and growing the plants from seeds.

My plan was to take a 10 gallon aquarium, cover the bottom with a mixture of washed sand and washed pea gravel, then build up soil on 2/3 of the enclosure and fill the remaining third with water. Then plant grass and weeds in the soil, and duck weed at the water's edge with an aquarium filter circulating and cleaning the water.

I know a snake can be perfectly happy on newspaper in a plastic container with holes(and that's where he'll stay until he's big enough to handle a larger enclosure), but I want to do my best to recreate natural habitat.

I want to recreate that little bit of childhood on my desk, a snake in the grass, catching fish and worms at the water's edge. I realize that a snake in tall grass is one I won't see very often, but that's part of the appeal to me, it will make it more satisfying when I do see him.

Anyway, my questions are.

Is my plan for a vivarium viable? If not, why? What changes do I need to make to make it work?
Is a full spectrum UV light sufficient for plants?
What is the best way to provide a basking spot in a vivarium?