Succulent plants have thick, fleshy leaves that store water. Some varieties flower while others only produce attractive foliage and stems. Most succulents thrive in dry conditions because too much moisture can cause the plants to rot. Rocky soil that drains quickly works well for most succulent varieties. You can grow them indoors in a dish filled with gravel, which provides adequate moisture drainage, although some soil is still necessary to provide nutrients and a medium for the succulent roots.
Fill a 3- to 5-inch-deep pot or dish with a one inch layer of gravel. Use a dish with no bottom drainage holes.
Sprinkle a tablespoon of powdered activated charcoal over the top of the gravel layer. Charcoal prevents odors from developing in the moisture trapped within the the gravel layer.
Place a peat-based potting soil on top the gravel, filling the dish to within 1/2 inch of the rim. Alternatively, make your own mix by combining two parts peat with one part compost.
Water the soil layer until it is evenly moistened throughout. Stick your finger into the soil mixture to judge the moisture level.
Plant the succulents in the potting soil. Set them so their roots are buried to the same depth. Spacing requirements depend on the specific plant type, but generally a 2- to 4-inch spacing is sufficient.
Water the succulents when the potting soil layer is completely dry. Provide only enough moisture to slightly dampen the soil. The excess moisture drains into the gravel bed beneath the soil.