Thank you, Sue. The reason I was asking about the gravel was because I was afraid I had forgotten something.
That bed will never drain down deeply. I did forget that soil next to a foundation, especially for buildings located on a slope, are mechanically compressed to a 98% density to provide stability for the the foundation.
I had planned to add a LOT of perlite to the amended soil to lighten the soil and will do some research to find out what the ratio should be when I back fill the bed to create the "perched water table" you mention in your post.
I do plan to put sheet metal between the soil and the wall so that there is no chance of moisture wicking up the stucco.
After more thinking, I've decided to use that bed as a "working bed" to start new plugs to allow them to grow larger root masses before being transplanted out into other parts of the garden and to test plants for heat tolerance. I won't be planting anything that needs deep watering.
To make it more attractive, I'll probably add some big rocks and possibly create enough shade for some other plants. Of course, I'll be testing those plants, too to see how they deal with reflected heat or heat absorbed by the rocks that might cause problems for those plants.
I'll use the gravel to repair the paths next to the sidewalks that have sunk due to subsidence caused by the drought. That will be gravel on top of gravel.
Thanks so much for the information you provided in your post. I feel comfortable going forward, now.
Smiles,
Lyn
