Answer: Geraniums (Pelargonium) are propagated by tip or stem cuttings (or seed). I do not believe a leaf cutting will work. Leaf cuttings either stuck into the soil or placed flat and pegged down will work with only a few plants such as certain begonias and African violet and quite often with succulents. Here is an illustrated article on leaf cuttings to show you what I am referring to as a leaf cutting.
I hope this answers your question.
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