Thanks y'all! You guys are great!
You know, I think I recall seeing "steppables" at the big box stores here, so will keep that in mind.
I will check out the various threads on this topic. I do know that I need to choose plants with similar needs, I.e., water, light, etc. I will have to keep in mind the scale of the garden in relationship to plant material. So, okay so far?
This will be an outdoor garden, so plant hardiness will factor in as well. Since I'm in zone 7, I plan to use material that is hardy at least to zone 6.
Onward and upward....
Susan