Dry out cuttings full of sap before planting them. With cacti, the drying period may extend to several days. Before planting geranium cuttings, let the cut surface callous overnight.

   Insert leafy cuttings one third to one half their length in the propagating medium. Do not let leaves touch the soil because this may cause them to rot. Make a hole in the medium with a pencil or your finger, then insert the cutting and settle it firmly in place.

   The length of petiole (leaf stalk) left on African violets, gloxinias, rex begonias, and other plants propagated from leaf cuttings varies. A one-inch petiole is likely to produce better plants than a cutting with a longer stem. When little or no petiole is left on an African violet leaf, the likelihood of mutation is increased. Given optimum conditions of light, temperature, and moisture, it takes five to six months to produce a flowering plant from an African violet leaf cutting.

   Rex begonia leaves can be handled exactly the same way as African violets, or it is possible to cut wedge-shaped pieces from a large rex leaf, each of which contains at least one prominent vein. When inserted in a moist rooting medium, each of these is capable of sending up one or more new plants. Gloxinia leaves with a half-inch or longer petiole can be rooted. After a time a new tuber will form at the base of the petiole. Eventually the old leaf dies, and a new plant grows from the young tuber.

   The most interesting way to propagate gloxinias and rex begonias involves making small cuts through the veins on the back of a large, healthy leaf. Lay the leaf on a moist propagating medium in a covered propagator. Plantlets will form at each place where the veins were slit. When these are large enough to handle easily, remove carefully with as many roots as possible, and transplant to individual pots of moist soil. Cover the plants with glass or plastic until they are strong enough to withstand the open air.

   Other plants which may be grown from leaf cuttings include sedums of all kinds, kalanchoes, and peperomias.

   Leaf bud or mallet cuttings of philodendron, ivy, and rubber plant {Ficus elastica) are made by cutting the leaves with a node and about an inch of stem below and directly above. The leaf forms a handle, the node and stem the head, hence "mallet cutting." Insert so that the node points up, and is slightly covered by the rooting medium.