You can test your own soil! Take two separate cups and add your soil sample to each. In one add vinegar and the other add some water, stir and add baking soda. If nothing at all happens your soil is some what PH balanced.
And you can interplant with veggies on the wall too! I REALL LIKE THIS IDEA. Plant the seeds of a loofa goard and reap the benefits of loofah scrubbies and a beautiful teepee for the kids back yard camping.