Your Crassula Tetragona enjoys a dry and arid environment. For this reason, it is best to only water your Crassula Tetragona when the soil is completely dry. Feel the top of the soil or remove your Crassula Tetragona from its pot and feel the soil. If there is any moisture at all do not water. When watering your Crassula Tetragona completely drench the soil to a point that the soil is completely moist. Your Crassula Tetragona cannot survive in temperatures below 30 degrees Fahrenheit.