The rootstock is the avocado plant that provides the roots and lower trunk. Choose a variety that grows well locally, so it is resistant to local disease and adapted to your soil. [3] X Research source Varieties with large seeds are usually best. [4] X Research source The scion is the piece of an avocado plant that you’ll graft onto the rootstock. Choose this for its high-quality fruit. You can take a bud or branch from an existing tree, or buy special scion wood or seedlings. (Growing it from a normal avocado pit usually won’t work. ) Just about any two varieties will join together. Some combinations don’t make healthy plants, but it’s not a big risk for a home garden. [5] X Research source
You have a longer window of “slipping” time if the plant gets plenty of water. Super hot or cold weather can end the slipping early, so if that happens, get your grafting tools out![7] X Research source Grafting wood instead? Spring or fall is still usually the best option. [8] X Research source Finding the perfect time for these can be super tricky, and depends on the graft method and even the individual tree. Get an experienced grafter to help you, or choose the moment when you see fat buds with a healthy green color. [9] X Research source
An extra- sharp knife Alcohol disinfectant (70%+) or any other disinfection method to use on the knife before you begin Grafting tape, budding strips, or flagging tape (or a cut rubber band as a last resort, but this isn’t great for budding or any outdoor graft) Cling film (optional)—ideally “Parafilm,” but normal PVC cling wrap also works. [13] X Research source
Make the “T” shape with a vertical slit about 1 inch (2. 5 cm) tall and a horizontal slit about 1/3 the way around the seedling (or branch). Gently twist the knife to separate the flaps of bark. [15] X Research source Avoid touching the cut surface with your fingers. [16] X Research source Cut a fat, green bud off the other plant. [17] X Research source Cut in a “shield” shape, with a point about 1⁄2 inch (1. 3 cm) below the bud and a horizontal cut about 3⁄4 inch (1. 9 cm) above it, deep enough to get wood as well as bark. Gently peel this off the tree, touching only the outer bark side. [18] X Research source Slide the “shield” into the T cut from above until the top lines up with the top of the “T. " Keep the flaps of the T-cut over the “shield” with the bud poking out between them. [19] X Research source
Small rootstocks (up to 1⁄4 inch (0. 64 cm) across), “wedge graft”: Shape the base of the scion into a wedge with two 30º angles. [22] X Research source Cut the rootstock horizontally, then cut a groove down through the center of the cut, a little deeper than the scion wedge. Fit the wedge firmly into the groove until the edges are flush. [23] X Research source Medium rootstocks (1⁄4–1⁄2 inch (0. 64–1. 27 cm) across), “whip-and-tongue graft”: Cut both the rootstock seedling and the base of the scion in matching, long slants, about 2 inches (5. 1 cm) long. Cut a groove down through the center of both cuts, then fit the pieces together so the grooves lock and the edges are flush. [24] X Research source
These are harder to secure in place than other grafted scions. You can attach them with thin flathead nails or tie them on with a strong cord. Grafting wax or pruning paint over the whole cut area helps protect it. [26] X Research source If you can, leave one “nurse branch” above the cut on the rootstock. This protects the new graft. You can prune away the nurse branch once the graft is healed.
For best results, follow up with Parafilm or PVC cling film around the whole area (including the bud if T-budding). This keeps moisture in to help the graft grow together. [28] X Research source Transparent grafting tape and cling film can overheat the plant. If you’re using them, keep the graft join out of direct sun or paint these materials white. [29] X Research source
First, use a disinfected knife to cut the seedling (or branch) about 13 inches (33 cm) above the graft. The part that’s left is the “nurse branch” that helps protect the new scion. Wait until your scion has grown a few new leaves, then remove the nurse branch right down to 1⁄8 inch (3. 2 mm) above the graft. If you grafted multiple scions onto one large branch or trunk, check and see which one looks largest and healthiest. Prune the others back to slow them down, then cut them off completely once the main scion is big and healthy. [33] X Research source You can also remove any wrappings that are left once you’re sure the graft is firm and growing. Grafting tape and Parafilm slowly degrade on their own, so you can leave those on. (Leaving the tape on too long is only an issue if the tree is growing rapidly. )
