An asexual means of plant propagation, grafting is the process of joining two compatible plant parts together to form a new and improved variety. One or more cuttings from a plant with better fruit production or flowering qualities are joined to a more durable and stronger plant. The resulting "cultivar" formed through this difficult process requires attention and care so it develops and grows healthy.
Grafting is the union of one or more cuttings (called scion) from one plant to the lower part of another (known as the rootstock). Some grafting techniques require one cutting while others require two, with each placed on a corner. The grafting method depends on the size of the rootstock. Bark and cleft grafts are used when the rootstock is larger than the scion. In this type, two or more cuttings are joined to the exposed surface for maximum cambium contact. Whip graft is suitable for plants with the same diameter, and usually features a single cutting joined to the rootstock. Plants too large for a whip graft but too small for the bark or cleft grafts are joined with the side graft.
For the graft to be successful, the cutting (scion) and rootstock must belong to the same botanical genus and species, even if the variety differs. Compatibility increases chances of success. Although plants of the same genus but different species can be grafted, the resulting plant is weak and often short-lived. Each scion must be 1/4 to 3/8 inches wide, at least a year old and have two to three visible buds on it.
Cuttings should be taken in the winter when the plant is dormant, and refrigerated for up 90 days until spring. It is always best to take more cuttings than required in case they get damaged.
Place the cutting in a cool, moist place immediately to prevent it from drying up. Store it in moist sphagnum in a plastic bag and refrigerate for two to three months until spring. Mist the sphagnum moss frequently to keep the cuttings moist during this time. Dip the exposed end in paraffin to help retain moisture, and cut this portion off before grafting.
Specific grafting tools ensure the success or failure of this horticultural practice. A sharp knife is essential for making straight, clean cuts through the bark and underlying cambium tissue of the selected wood. Dip the knife in alcohol solution prior to use so it is clean and free from bacteria. Grafting wax is wound around the joint between the cutting and rootstock. It protects the wound and encourages both plants to unite and grow as one. Budding strips and nails apply pressure on the grafted area and ensure maximum contact.