Lighting is very important to get your plants to flower and grow properly.   Natural light is fine for an African Violet as long as it does not get direct sunlight.  Direct sunlight will burn the leaves and potentially kill the entire plant.  Fluorescent lighting is very good with care not to get the plants too close to the light source.

If your African Violet gets too much light, you will notice hard brittle leaves that are generally stunted.  Too much light can even burn the plants.  If your African Violet gets too little light, you will notice long petioles and large thin leaves.

Growers can purchase multi-layer bench systems, but these are very costly.  These shelving units can be easily built with PVC or a simple wood frame.  Dual bulb fluorescent fixtures are attached at each shelf level to provide the needed lighting.   While there are fluorescent bulbs available that specify 'growing lights',  studies have shown that these lamps don't do any better than using cool-white or warm-white bulbs.