Grafting a plum tree involves implanting a live cutting from one variety of plum into another similar variety that acts as a root stock. The root stock nourishes the cutting until the two merge into one plant. From then on, that grafted branch will bear fruit that is genetically identical to the tree it was taken from. A form of grafting called budding is the preferred method for grafting plum trees. Budding does requires some preparation and special treatment. The technique called 'T' budding is perhaps the easiest way to graft a plum tree and generally has a high level of success.
Creating the Graft
Collect sticks with buds from healthy branches of desired plum trees in the summer when the bark of the trees will slip easily from the inner wood. Choose branches from the previous season's growth up to 1/2 inch in diameter.
Look for bud sticks that are mature and brownish colored. Remove the bud stick from the tree and clip off any leaves on the bud stick. Wrap the bud sticks in a damp cloth to prevent them from drying out.
Remove each bud to be grafted from the bud stick by making a cut under the bud. Start about 1/2 inch below the base of the bud and end 1/2 inch above it. Cut the top edge of the bark square to form a shield shape.
Remove the underlying wood, once the bud is cut from the stick, leaving only the bark and the bud itself. Ensure that the newly removed bud does not dry out.
Make a 'T' shaped cut through the bark of the trunk on a young root stock tree. Be careful not to cut too deeply.
Lift the corners of the cut with the tip of the knife to loosen the bark from the branch.
Slide the tip of the bark that the bud is attached to into the 'T' cut so that the bud's bark is under the bark of the root stock tree. Insert the bud until the top of the shield meets the cross cut in the 'T'.
Wrap the trunk with rubber band strips to hold the bud in place. Do not cover the bud.
Check the bud after 2 weeks to see if the graft has taken. The bud should remain dormant until next spring, when it will sprout. As the bud starts to grow, cut off the stock above the graft. Remove any shoots sent out by the root stock to encourage the new bud to grow.