Why you shoud propagate an African Violet?

So the best way to propagate an African Violet is to knock the parent out of its pot onto a few sheets of newspaper and carefully reach in and tease those suckers out. You may also need a sharp pocket knife to cut through the root ball to detach it from its parent. Early Spring through Mid-Summer is the time for this project, the earlier in the Spring, the better.

Once you have divided the plant, plant the babies in a light soil mixture with plenty of peat, perlite and vermiculite. Miracle Grow Potting Soil (Damiana), Cornell Mixture and Schulz Potting Soil Plus are all readily available and good for this. Use plastic pots. African Violet leaves rot in contact with the moist rim of a terracotta pot. If you use clay, wax the rim or use decorative foil around the rim to stop the problem.

Use the smallest pots you have, not the largest. The damaged roots will need to heal and expand before they can use all that soil. Extra encourages rot. Don't forget to add a layer of pebbles or broken pot to the bottom of the pot for drainage.

source - http://www.associatedcontent.com/article/5666148/how_do_you_propagate_an_african_violet.html?cat=32