Succulents, cacti and other dry arid climate plants just flourish when they're around decomposed granite. Why? Because DG is made of aged granite that has begun to crumble part and in nature desert plants literally grow out of DG.
It's far superior to other products that just use a fine grain sand and call soil "cactus mix". Those types of sand resemble the stuff in a sand box. It's small particle size actually suffocates the roots and compacts down overtime. DG is excellent because it has a varied particle size. Also it's overall weight is needed to help anchor desert plants that have a shallow root system.
 
Use DG to top dress your succulents and cacti. This will anchor the plant to keep it stable in the pot, improve moisture retention and protect your plants root system.
 
Use DG as an amendment to your soil for when you need to repot a desert plant and only have all purpose soil on hand. Toss in about 1 cup of DG for every 6 cups of soil