Place an inch-thick layer of small pieces of clay pot or coarse gravel at the bottom of medium-sized pots to aid drainage. Prepare one pot for each plant.
Mix about two parts general-purpose potting compost with one part perlite or coarse sand to produce a well-draining soil.
Transfer each African violet from its original pot to a new one. Pack the compost mixture around the plant.
Place a layer of coarse gravel on a tray or plant saucer. Place the pots on top and water them sufficiently to dampen the soil.
Position the pots on a windowsill that faces north or east. Alternatively, position them about a foot away from a fluorescent lightbulb. Switch the light on for 12 hours a day. Sufficient light promotes flowering.
Move your plants off the windowsill and into the middle of the room at night unless you have well-insulated windows.
Mist the leaves lightly once or twice a week.
Fill the tray or saucers up with water a couple of times a week. African violets need plenty of moisture, but soggy soil causes problems.
Check the bottom of the pot about once a month. When you can see roots through the holes, transfer the plant to a bigger pot.
Fertilize the violets with a liquid houseplant fertilizer as per the instructions. Use the minimum amount recommended because too much fertilizer might promote leaf growth but discourage flowering.