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Choose your cultivar and your rootstock. Amputate your rootstock. Cleave your rootstock. Prepare the scions. Insert the scions into the rootstock. Seal the graft. Look after the graft.
Scions should be two dormant, or not currently sprouting, twig of about a foot long containing three to five buds. Rootstock should be straight, smooth, vertical branches 12 inches (2.55.1cm) in diameter. Cleft grafts should be performed right before the bark of the rootstock starts slipping (being easily peeled off) in spring. This graft is usually used for top working (changing the type of fruit) of a mature tree by being performed on a number of branches. Choose a point below which the branch is straight and blemish-free for six inches and then make a clean perpendicular cut, removing the rest of the branch. Be careful not to tear or split the branch or bark. Be sure to leave a branch that has sprouted nearby to keep nutrients moving up the tree. Use a cleft-graft knife or a hatchet to split the branch straight down the center for about 6 inches (15.2cm). Remove the tip and the base of the scion. Beginning just below the bottom bud, make a sloping cut on either side of the scion that reaches all the way to the bottom. Using a large screwdriver or small chisel to hold open the cleft in the rootstock, insert a scion into either side of the cleft. Make sure once again that the green layer of the wood, not the bark, is aligned. No cut surface on the scion should be visible above the top of the rootstock. Pour grafting wax or asphalt water emulsion over the area to seal all cut surfaces from drying and germs. Check the seal again the next day to make sure no holes have become exposed. Keep removing all growth below the graft. Once one scion shows more promise than the other, leave that one as is while pruning the less successful graft. Two summers after grafting, remove all but the strongest scion.