Grafting is a term used to describe a common propagation practice in gardening. It is when you take a branch from one tree and connect it to another so it can grow there. It is often used in fruit trees to grow healthy fruit, sometimes of a different variety than the original tree. There are several grafting techniques; however, the "budding" graft is most used in citrus trees, including lemons, and has proven to be one of the most successful grafts, especially for beginners. Graft lemon trees in the spring or early fall.
Remove a branch, called the scion, from an existing lemon tree that has proven to bear good fruit. Choose a healthy, disease-free tree, and a branch that has several buds. If you are not grafting immediately, place the scion in water or wrap it in plastic.
Slice the buds off the scion, along with a sliver of wood and bark. Start about 1/2 inch below the bud and end about 1 inch beyond the bud. Store it in water if you are not grafting right away. Graft as soon as possible so the buds do not dehydrate.
Prepare the rootstock--the young lemon tree on which you are grafting. Graft branches that are ¼ to 1 inch in diameter on larger lemon trees, if desired. Cut a T-shape about 8 to 12 inches above the soil on a young rootstock, or 8 to 12 inches from the main branch of an older tree. Cut the vertical part of the T 1 inch long, and the horizontal part a third of the distance around the tree (e.g. 1/3 inch on a tree that has a diameter of one inch). On the vertical cut, gently twist the knife to open the bark up a bit for the bud to fit.
Slide the longer side of the bud cut down into the T cut so the bud is at the top of the T, sticking out. Inside the T, position the two pieces of cut wood so they are touching, or they will dry up and not grow.
Wrap the graft together using budding rubber, a wide rubber band or transparent tape. Do not cover the bud. Do not seal the area with grafting seal, as you would with other types of grafts.