If the succulent is still inside the plastic pot, it's a good sign. A small pot is better because it can hold less water. Its thick stems reach height before its weight causes it to bend. You should plant your cactus in well-draining soil, in a tall planter. A popular potted cacti, "Old Man Cactus" is tall and cylindrical, covered from top to bottom in modified spines that resemble hair. These long spines look like the shaggy hairs of an old man.