TN Outdoor Wedding/Reception Sites

I`ve always dreamed of having a beautiful outdoor wedding and reception, but me and my fiance are paying for our whole wedding on our own. We don`t want to go broke for our wedding, but we`d like it to be a nice and romantic day. The biggest obstacle we`re having is finding a good outdoor site that doesn`t charge too much. Does anyone have any suggestions for a place in middle tennessee?