Huernias require a potting mix with excellent drainage. A succulent plant mix of 50 percent pumice or perlite, 25 percent peat or organic mulch, and 25 percent sand helps prevent rotting and overwatering. Roots experience dieback in cool-season dormancy, so plants grow best in shallow containers that allow the soil to dry out quickly. Using clay pots further helps soil from staying too wet. An underlayment of coarse gravel below the soil mix also improves drainage. In climates with damp cool summers, a layer of gravel between the plant and the soil mix also helps prevent the stems from staying too moist.