Have you ever seen an apple tree with bright-red Jonathan apples on one limb, Golden Delicious apples on another, and dark-red Winesaps on a third and wondered how that could be? The answer is actually quite simple -- grafting.
Grafting means joining parts of two or more plants together so that they grow to be one plant. Grafting sometimes occurs naturally when two plants come in contact, but it is a common practice in orchards and other growing operations. A grower joins a cutting from one plant to a root, or to a stem bearing roots, of another plant. The part implanted is called the cion. The plant receiving the cion is the stock. The cion retains the characteristics of the plant from which it is taken. The stock supplies food and water for the growing plant.
Apple trees are not the only plants that can be grafted. All fruit trees can be grafted, as can grapevines, rosebushes, lilac bushes, and most other plants with woody stems. Many soft-wooded plants can also be grafted, including the tomato and potato. Dahlias, peonies, cacti, and various other soft-wooden flowers may be grafted each within its kind. Only closely related plants can be grafted, however.
Reasons for Grafting
Fruit trees grown from seeds are not likely to bear fruit just like the fruit that the seeds came from. This is because the seed is likely to have two different trees as parents and will therefore not grow into a tree exactly like either parent. The only guaranteed way of getting a new Golden Delicious apple tree is to graft a twig from a Golden Delicious tree on to the stem and roots of some other kind of tree -- usually either another apple tree or a quince tree. It is by grafting several different varieties of apple trees onto a single stock that an orchard is able to produce an apple tree that bears several different varieties of apples.
Grafted trees grow faster and bear fruit sooner than trees raised from seed, because the stem and roots already have a good start.
Grafting can also be used to change the habit of growth. For example, trees can be dwarfed by grafting cions of vigorous plants on less vigorous stocks. Sometimes plants that do not thrive on a soil are grafted on stock that grows well on that particular soil. The time of bearing of a fruit tree, both in years and season, can also be changed by grafting.
Another advantage of grafting is that twigs of trees that are easily hurt by disease or insects can be grafted on trees that are hardier and/or more resistant.
Kinds of Grafting
In Bud Grafting a single bud is grafted onto the stock. Fruit trees, roses, and many ornamental plants are propagated by budding. The cion is usually a mature bud cut from a twig of the current year's growth with a bit of bark and a bit of wood. The bud is inserted in a t-shaped wound in the stock by pushing it down, using the leafstalk as a handle. When the bud has begun to grow, the top of the stock is cut away close to the graft.
Whip Grafting is most commonly used when the stock is a root. This has long been the favorite method of propagating apples and pears. The rootstocks are one or two years old. They are dug in the fall and stored until late winter, when grafting begins. Both stock and cion are cut diagonally with a smooth cut. A vertical cleft is then made in both root and cion, so that they can fit closely. The tongue of the cion is pushed into the cleft of the stock. The joint is tightly wrapped with waxed yarn made by soaking a ball of yarn in hot grafting wax. The grafts are then tied in bundles and stored, as were the cions, until planting time in the spring.
Cleft Grafting is used in grafting old trees. A branch 1 to 2 inches in diameter is cut off squarely. It is then split and a cion with a wedge-shaped butt is inserted into the cleft. The cleft is closed around the cion and covered with grafting wax.
Inarching is a process of grafting two plants, each of which is on its own roots. To graft by inarching, one removes a small area of bark on each plant and ties the stock and the cion together. When the union is complete, the lower part of the scion is cut away.
Bark Grafting is a way of repairing large trees. The bark is opened and the cion is pushed down between the bark and the wood. The cions are cut thin, held in place by a waxed bandage, and covered with grafting wax.
In Splice Grafting, cion and stock are cut across diagonally, laid together, and kept in place by tying with waxed string.
Annual Budding is used in grafting trees with thick bark.
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This page was last updated on 03/20/2014.