I absolutely love African violets and have for decades. I’ve grown many from just one leaf, the one pictured here is one of them. You can do so by just putting a leaf with a 3″ stem in water, which is how I have always done it, or putting it in dirt. I prefer the other method, putting the leaf in a clear container so that I can see the roots develop. Once they have developed, I then put it in African violet soil.
Violets are very inexpensive to purchase and once they bloom, the blooms last up to six weeks at a time. There are so many varieties too!