Yet, the plants are alive! In this picture there is a mandarin tree, a thin pomegranate tree, a large succulent, and nitrogen - fixing clover. I credit the success of these plants to the rocks that shade their soil. This prevents moisture loss and hardening of the soil despite my neglect.
The first thing I did to prepare this area was make sure the ground was well watered from rain we had in the winter. Since it rains in the winter, a bunch of clover had grown here. I pulled that clover, chopped it up with a knife, and laid it over the soil. I then covered the area with cardboard that I had soaked in a tub of water. I left the cardboard for a couple of months, occasionally watering it. The neighbors must have thought I was crazy to water cardboard!
The soil was very nice after that. I found the biggest earthworm I have ever seen there when I dug into the ground.
When using mulch, you can put a special fabric down to prevent weeds from growing. I did not do this because I wanted to plant seeds and have a variety of plants growing to improve soil health. So I just placed my rocks down, slightly overlapping. I used fist-size rocks that I got for free from someone who was redoing their backyard.
The first summer I planted "Seeds for Kids" from bountifulgardens.org. This is a mixture of non-toxic, non-GMO seeds. I also planted fodder radish from the same company, since it is known for being able to break up clay, as well as sunflower seeds from my local nursery.
I was a bit lazy about watering this area. Despite this, I ended up with a few random plants. Two sunflowers grew. I am so glad they did. From those two sunflowers I gathered many more seeds than is provided in a single packet at the store. I also had a couple of large radishes grow from the radish seeds I planted. I gave those to a neighbor who actually knows how to cook. From the kids seed packet I had a couple of squash and a few bean and black-eyed peas grow. I gave the neighbor the squash for her family. The beans and black-eyed peas I kept to grow again later.
That was a pretty good crop considering my failure to water the area sufficiently in an area of little to no rainfall in the summer. I highly recommend using small and medium rocks as mulch. The heat that might be absorbed by the rocks is more than made up for by the benefit of the rocks in shading the soil.
I know have two dwarf citrus trees and a pomegranate seedling in that area. Having a well established plant may be helpful if you can't (or can't remember to) water your plants. Drought tolerant plants like rosemary may also work well in the heat.