The Stenocereus pruinosus succulent is also known as the Gray Ghost Organ Pipe. Well, the most common sign is discoloration caused by over or under-watering. A: Yes, you can touch your succulent plants if you want to inspect for signs of pests or diseases. These are signs that your succulent has outgrown its pot. Some aficionados prefer to place a saucer of water under the pot and allow the cacti roots to pull the water up. It is safe to water if it is dry after being removed. Keep away from direct sunlight, mist every few days or when the soil feels dry.