Propagating African violets by leaf
African violets are very easily propagated from leaf. Even inexperienced growers can quickly produce additional plants and expand their collection.
Step 1: Remove and trim leaf. Remove a fresh leaf from the plant that you wish to propagate. It's best to use a mature leaf, but not one that's old and tough. Using a sharp knife or razor, trim away the top of the leaf blade. This isn't a necessary step, but it will encourage faster production of roots and plantlets from the leaf when it's rooted, and will stop the leaf itself from growing.
Step 2: Cut leaf petiole. See photo at right. Cut the petiole (i.e. leaf stem) at a 45 degree angle, cut-side facing up, to about 1/2" in length. By cutting at an angle, this will encourage more root and plantlet production, and they will more likely appear in front of the rooted leaf, rather than hidden behind or underneath it.
Step 3: Root the leaf cutting. See photo at left. Fill a small pot with your rooting medium. This mix should be very light and porous. Our rooting mix is 1 part Pro-Mix (a soil-less peat an perlite mix) and 3 parts coarse vermiculite. Any mix at least this light is acceptable (some growers use only vermiculite or mix with perlite). The mix should be moistened (not too soggy, or the leaf will rot). Make a narrow hole in the mix--we like to use a "swizzle stick" for doing this. Push the leaf petiole into this hole, up to the bottom of the leaf blade (as shown), and firm-in rooting mix around it. More than one leaf cutting may be rooted into a single pot, if there's room. Label the pot and place it into a clear, covered container or plastic baggie. Then, place this in a bright place with moderate temperature--no direct sun or very warm locations, since this may cause the leaf cutting to rot or burn.
Step 4: Plantlets at 12 weeks. One or more plantlets will begin to develop from the cut end of the rooted leaf's petiole, and will make their way above the soil. Those pictured are ready to be separated and planted now, but we usually wait 4-5 months, since the extra time allows more plantlets to grow from the cutting. The plantlets also will be just a bit bigger, easier to handle, and more likely to survive their transplanting.
Step 5: Separate plantlets from leaf cutting. See photo at right. When plantlets are large enough for you to comfortably handle them, they can be separated from the "mother" leaf. Remove the cutting from its pot, firmly grasp a plantlet, and gently pull it away from the leaf cutting. If your rooting mix is light, and not overly soggy, this should be easily done without need for a knife. Don't worry too much if your plantlet doesn't have many (or even any) roots--so long as the plantlet itself is healthy, it will produce roots when it is potted.
Step 6: Prepare pot for plantlet. See photo at left. Fill a small pot (2" or 2 1/4") with your regular soil mix. Make a small hole deep enough to hold the plantlet to be potted--we like to use an old pencil to do this.
Step 7: Pot plantlet. See photo at right. Gently push plantlet into hole and firm-in soil around it. Plantlet should be placed deep enough into soil so that none of the bare central stem or 'trunk' is exposed, but not so deep as to bury the tiny growing point in the center of the plant.
Step 8: You're done! Label the plant and lightly water. Larger plantlets can be immediately placed amongst your other violets. If the plantlet is still very small and/or has few roots, you might want to place it into a clear, covered container or plastic baggie. This will provide a small "terrarium"-like environment, and will protect it while it gets established. Remove it from this container in a few weeks.