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My Propagation Techniques 
Leaf Propagation Leaf propagation is quicker than hybridization (creating seeds by combining two plants) and done if you want to create an exact duplicate of a plant you already own. First, I select leaves from the middle of the plant, not the lowest leaves that are older or the ones near the crown which are newly formed. Cut the stem at approximately a 45º angle with a sharp knife, wet the bottom of the stem with water and dip in rooting hormone. Tap off any excess and make a hole about the width of a pencil and 3/4 inch deep. Insert the leaf at an angle and water to merely dampen the soil. The temperature in the propagation area should be about 72-78º F. Cooler than this will prolong the time it takes for the leaf to put create roots and new leaves, and warmer than this will promote rot. Violet leaves absorb water through the atmosphere as well as from the stem, so keeping the humidity high by covering with plastic is essential. Soil Equal mixtures (1:1:1) of perlite, vermiculite and peat moss are typically used for rooting African violet cuttings. Some use a 1:1 mix of perlite and peat moss or vermiculite and peat moss. Many people use only vermiculite to root cuttings. In all cases, the cuttings should be covered with plastic to retain moisture, which reduces leaf wilt. Trays I find that the plastic "grow trays" with individual cells that are sold at many discount and garden stores are very handy for propagating African violet leaves and are quite reasonable to buy. Some have 72 cells and are available without prepackaged soil, so I can add my own African violet mix. I have tested other propagation techniques, but the grow trays seem to work best for me because of the controlled humidity level. The plastic cover that is sold with the tray keeps in moisture, and for propagating leaves, it is critical to keep the humidity level high. This cuts down on leaf wilt when they are first put down, before roots are developed. The soil also stays moist and there is virtually no additional watering needed for five or six weeks. When I check the tray, I always find that there is moisture buildup on the clear lid, so I know that there is sufficient humidity inside. If you have only a few leaves to put down, you can use plastic pots and cover them with a baggie to retain moisture. 
After about four months, many plantlets are ready to be transplanted to their own pots, which I continue to keep in the same temperature environment to minimize any stress possible. A good rule is not to transplant to their own pots until the leaves are at least the size of a dime (green leaves) or the size of a quarter (variegeated leaves). Plastic Bags Propagating in plastic bags uses less space and less soil mix. Buy freezer bags at any supermarket or discount store -- the kind that are re-sealable. I buy those that have a space to write on so I can jot down the name of the violet and the date that I placed the leaf in the soil mix. Put a small amount (about 3-4 heaping tablespoons) of potting mix in the corner of the bag and moisten slightly. Use a small paper punch to make a hole in the top of the bag to let in a little air. Make your leaf cutting and apply a small amount of rooting hormone to the end. Insert it in the soil mix and zip up the bag's top. By using "bull-dog" clips, I can clip three at a time to a line that I have strung across a window that lets in bright light, but not too much direct sun. It is more difficult to control the temperature with this method, and although it takes up less space, I have more leaf loss. If I am trying to leaf propagate a plant that I consider to be one of my more valuable ones, I do not use the plastic bag method. 
Variegated Leaves Leaves with white, pink or cream coloring produce less chlorophyl than those that are totally green, and plantlets should be allowed to grow larger than totally green plants before moving to their own pots. Sometimes a cut leaf will produce plantlets that have no chlorophyl at all, and will be entirely white or pinkish in color. It may be possible to coax these plantlets to produce chlorophyl by adding an African violet fertilizer mix to water them with. As they grow larger, most produce chlorophyl on their own, but even established variegated plants will produce less than completely green plants. Below: (left) A variegated leaf grouping at two months with some leaves showing very little chlorophyl. As they grow, more chlorophyl may develop as the leaf is exposed to more light. Right: At approximately three months, plants showing more green and healthy enough to no longer need the mother leaf.   Chimeras Chimeras are an exception and will not "bloom true" when propagated through leaf cuttings. In other words, you will not get a plantlet that will have the same color, or characteristic bloom as the parent plant. For this reason, chimeras can only be propagated through suckers, making their multiplication slower. To encourage the growth of suckers which can be grown into plantlets, make a clean cut on the stem, one third of the way from the bottom of the plant. You will be cutting off 2/3 of the plant growth. The remaining stub (with some leaves attached) should be placed in a temperature controlled area, and within a couple of months, new suckers should be growing from the stub. After about three months, these can be coaxed away from the main plant and planted individually. The top of the plant that was cut off can also be rooted in water to create a new plant as well. Propagation By Seeds (Hybridization) Hybridizing African violets is done by transferring pollen from one plant to the pistel of another. Every violet blossom has both anthers (pollen sacs) and a stigma with pistel (the female part that accepts the pollen). The pollen sacs are yellow and visible to the eye, and when ripe, can be broken open to release a whitish powder. They can have a leathery outer surface and it is often necessary to break them open with your fingers or a small knife. The pollen can be transferred by the end of your finger or a small object such as a toothpick to the pistel of the blossom of the receiving plant. If pollination is successful, within a few days a swelling will begin to develop at the bottom of the blossom with the pistel. This is the seed pod. In five to six months, the blossom and the stem should be totally dried, and the seed pod ready to be harvested. Keep careful records of the plants that you cross, labeling them when you divide or repot them. Care in labeling is necessary if you wish to register a new plant with the African Violet Society of America (AVSA) or just to serve as a way to refresh your memory as to which ones you crossed in the months to come. Keep in mind that it is necessary to propoagate the new plant through three generations of leaf cuttings, checking closely to see if the new plants are exact duplicates of the parent plants, before attempting to register this new hybrid with the AVSA. The plant registration and master plant list chairman is: Joe Bruns, 1220 Strtford Lane, Hanover Park, IL 60133-2667. E-mail: jbruns@qwip.net. 
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