Create new orange trees from your favorite variety by taking cuttings to propagate into new plants. Cutting propagation is preferred for oranges over growing from seed for several reasons. A cutting grows quicker than seeds and produces a strong plant with more disease resistance when grafted onto hardy rootstock. Propagated orange trees are ready for planting outdoors in the home garden once the graft point has sealed and the cutting begins to grow, generally one year after planting in a container.
Rooting an orange tree cutting is more desirable for orange tree propagation over starting a seed taken from an orange. Propagating a seed doesn't guarantee the fruit will be identical to the parent tree, due to cross-pollination. Rooting an orange tree cutting ensures the fruit produced matches the same tree genetics as the parent tree. Grafting a rootstock onto the cutting doesn't change the genetics or affect the fruit production. Hardy rootstock is often taken from an orange variety that has less desirable fruit production but strong growth characteristics.
Propagating orange trees with cuttings involves taking softwood and rootstock cuttings. Softwood cuttings are pieces of new branch growth cut from the tree from late spring through early summer. The growth is soft, may have a green tinge and should be about 6 to 8 inches long with at least two growth nodes. This cutting is grafted, or attached, to a rootstock cutting that is 3/8- to 1/2-inch diameter and about 6 inches long. Tree cuttings can be stored in a refrigerator by wrapping them in moist paper towel for up to three weeks, until there is time to properly plant them.
T-budding propagation is the common method used for orange trees. It involves making a T-shaped cut on the top point of the rootstock so there is a 1-inch opening where the softwood cutting fits in. A cut made on each side of the bottom end of the softwood cutting allows the root and branch to fit together. The rootstock and cutting are held together with a rubber band around the T-graft point. The join is dipped into propagation wax to protect the area while it bonds and heals.
The propagated cutting is planted into a container filled with sterile potting soil so the join is 1 to 2 inches above the soil line. Planting immediately limits moisture loss and improves the chances of successfully rooting the cutting. Orange cuttings prefer filtered sunlight during the rooting process, instead of direct or full sunlight. The soil must be kept moist during the propagation process.
Purchase hardy rootstock specimens at garden supply stores in the bare-root plant area instead of removing a root section from a tree in your garden. This will guarantee an adequate size and disease-resistance properties for propagation success.