Plum trees grow from seed or propagate through cuttings or grafting. Plum trees from seed may not grow true to seed if the plum is a hybrid variety. Propagating by plum tree cuttings is more reliable and produces a fruiting tree much sooner. Plum trees from cuttings do as well as grafted trees and come into production sooner. The recommended method of plum tree propagation is from cuttings. Take a cutting from the plum tree in the spring when the first flower buds appear.
Choose a shoot approximately an eighth-inch in diameter and cut off a piece 6 inches long. Remove all but the uppermost three or four leaves.
Remove the bark from the bottom inch of the cutting.
Place the cutting in a damp rooting medium made of equal parts peat and clean sand.
Maintain high humidity with a humidifier or by misting the cuttings. Keep the rooting medium moist but not wet.
Allow five to seven weeks for the cuttings to develop a good root system. When the roots are established, gradually reduce misting, allowing the plants to harden off. Water only when the surface of the rooting medium dries out.
Transplant the cutting into a pot of potting mix. Grow the plum tree in the pot in a sheltered place for the first year, then transplant the year-old plum tree into the ground.