A petiole is a stalk of the leaf. Rex begonias and jade plants are commonly propagated by placing the leaf in the medium. Rex begonia should be wounded by cutting the main veins on the underside of the leaf before placing the leaf surface flat on top and in firm contact with the propagation medium. To hold the leaf next to the rooting medium, pin the leaf down with small, wire hairpins, bent paper clips or toothpicks. New plants will form where the cuts have been made in the veins of the leaf.
African violet is propagated using a single leaf with part of the leaf petiole attached.
Shorten the petiole to 1 inch long. Stick the leaf petiole upright in the propagation medium just like the stem of a cutting. Roots and shoots form at the petiole's base. The swordlike leaves of the snake plant or Sanserveria can be cut into sections. While cutting the leaf into sections, remember which end of the leaf is the bottom, because after the tip of the leaf has been removed the rest do not have distinct markings to determine which end should be placed in the rooting medium.