I wish I could go 'Wild' like you FF. I'll start looking around. I'm thinking a State Park might be a good place. The best places are probably inaccessible unless you're a Real 'Outdoorsman'. I bet you spend a lot of time outside? I've always wondered how 'flushing' the body with Green Juice would feel, but I can only produce 8 ounces (max.) of Wheatgrass Juice each day.
As far as my fertilizer goes, I use a liquid mix that I prepare in my Blender. It includes Carrot Tops and Bottoms (from carrot juicing), Clay, sometimes Celery scraps, and plenty of water. It makes my wheatgrass Sweet.....WY
P.S. By the way, Celery is of the Carrot Family. I like Celery Juice after taking wheatgrass juice.