Where I live, we have NO rocks in our dirt....just this horrible clay that shifts with the weather. This shifting causes cracks in walls and doors won't shut, especially in the summertime. I have a privacy gate that I like to close, but it's impossible to do so in the summer. I just have to wait for cooler weather.
Many people have major foundation problems here, but one thing I began doing a long time ago is to place soaker hoses around the perimeter of my home and then turn the water on and allow my home to absorb this slow dripping of moisture. It does help reduce foundation problems. Also, never plant azalea bushes or plants that will suck the water out of the ground. That will just add to your foundation problems.