In that case, Jimmie, have you looked at using Earth Boxes? Once you set them up, all you need to do is make sure they get enough water. You put in soil, fertilizer and maybe dolomite, moisten, plant, cover and then just water. Mine are on micro-irrigation on a timer so I don't even worry about watering.
I have a large raised bed, but like you, don't have a lot of energy for amending any more. So all my winter veggies are now grown in Earth Boxes. I get better yields each year from them than I ever did growing in the ground or raised beds.
Other than shrub or tree fruits, I can't think of another perennial edible plant offhand. Pomegranates are beautiful, and have nice nutritious fruits. Not sure if they would be hardy for you.
