Japanese maples are often used for bonsai.
Japanese maples can be grown from seed, but the resulting seedling is not likely to have the form, color or leaf shape of the parent plant. The only reliable way to reproduce a Japanese maple cultivar is through grafting or budding. Maples are considered more difficult to graft than some other trees. One useful technique is called a side-veneer graft. This technique leaves top growth on the rootstock to nurture both the rootstock and the graft until the grafted variety starts growing.
Purchase seedling Japanese maples for rootstock. These trees can be from 1 inch in diameter to 5 or 6 feet tall. Pot up the rootstocks, and keep them in the shade until they are established and producing new leaves.
Select the variety of Japanese maple you want to graft onto the rootstock. Cut 1/4- to 1/2-inch twigs from the selected variety after the wood has matured. These twigs are called scions. They can be harvested from late July until new growth begins in the spring. Place the cuttings in a labeled plastic bag, and put them in a cooler.
Select a smooth spot on the trunk of the rootstock at least a foot from the bottom. Make a slanting cut almost to the center. Cut off about two-thirds of the flap on the outside of the cut.
Remove all but two or three of the leaves from the scion. Make a 3/4- to 1-inch-long sloping cut at the base of the scion. Make a short, 45-degree cut opposite the first cut, to make a wedge-shaped end on the scion.
Push the scion wedge into the cut on the rootstock, placing the shorter cut next to the flap, the longer cut toward the trunk. Align the cambiums of the scion and rootstock.
Wrap the graft with a rubber grafting strip or grafting tape. Put a plastic bag over the scion, carefully pull it down over the graft, and secure with a twist-tie or a clothes pin. Place the grafted tree in the shade.
Check the grafts in 7 to 10 days. Black leaves and wood indicate the graft did not take. Remove the scion, and wrap the cut area. If the rootstock survives, you may be able to try another graft at a different location on the same rootstock.
Leave the bag on successful grafts for three weeks. Gradually untie, then remove the bag over the next two weeks. When the buds on the scion begin to swell, cut off the top of the rootstock above the graft with the Bonsai cutter, and move the plants to a larger pot.
The cambium is the thin green layer under the bark. If the scion cut is smaller than the rootstock cut, align one side. Do not put the scion in the center of the cut.
Several grafts can be made along the rootstock trunk. For weeping varieties, several scions should be grafted near the top of a 5- or 6-foot tree.
Doxon, Lynn. "How to Graft Japanese Maple Cuttings." Home Guides | SF Gate, http://homeguides.sfgate.com/graft-japanese-maple-cuttings-47900.html. Accessed 23 April 2019.