Grafting is a horticultural technique that allows you to create new fruit trees by joining two different plants together. By grafting, you can combine the best characteristics of two varieties, such as fruit quality, disease resistance, and growth habits. Grafting can also help you repair damaged trees, improve tree health and productivity, and propagate rare or heirloom cultivars.
Key Takeaways
- Grafting involves attaching a scion, or a small cutting from a desired fruit tree, to a rootstock, or the base of another tree.
- The scion and rootstock must be compatible and closely related species, such as apple to apple or peach to plum.
- The best time to graft fruit trees is late winter or early spring, before the buds begin to swell.
What You Need to Know About Grafting
Before you start grafting fruit trees, there are some basic concepts and terms you need to understand.
Scion
The scion is the part of the graft that determines the fruit variety and characteristics of the new tree. It is usually a small cutting taken from a mature fruit tree with desirable traits. The scion should have at least three to five buds and a diameter of about 1/4 to 3/8 inch (6.35 to 9.5 mm). The scion should be collected in late winter or early spring while the tree is dormant [1].
Rootstock
The rootstock is the part of the graft that provides the base and support for the new tree. It determines the size, vigor, and disease resistance of the new tree. Different rootstocks have different characteristics, so choosing the right one for your desired fruit tree is important. For example, some rootstocks are dwarfing, meaning they produce smaller trees that are easier to manage and harvest. Other rootstocks are more resistant to certain pests or diseases [2].
Compatibility
Compatibility is the ability of the scion and rootstock to grow together and form a successful graft. Compatibility depends on the genetic similarity of the two plants. Generally, plants within the same species or genus are compatible, while plants from different families are not. For example, apple trees can be grafted onto crabapple rootstocks, but not onto citrus rootstocks [3].
Cambium
Cambium is a thin layer of living tissue between the bark and the wood of a plant. It is responsible for producing new cells that increase the diameter of the stem or branch. Cambium is essential for grafting because it allows the scion and rootstock to fuse together and exchange nutrients. For a successful graft, the cambium layers of both the scion and rootstock must be aligned and in contact with each other [4].
Healing
Healing is the process of forming a strong union between the scion and rootstock after grafting. Healing depends on several factors, such as temperature, humidity, light, and wound protection. Healing usually takes several weeks to months depending on the type of graft and the growing conditions [5].
How to Graft Fruit Trees: Step by Step Guide
There are many methods of grafting fruit trees, but here we will focus on four simple ones: whip grafting, cleft grafting, bark grafting, and bud grafting. Each method has its own advantages and disadvantages depending on the type and size of the scion and rootstock.
Whip Grafting
Whip grafting is one of the most common methods of grafting fruit trees. It is suitable for scions and rootstocks that are similar in size and have diameters of less than 1/2 inch (12.7 mm). Whip grafting is often done indoors with dormant rootstocks dug out of the ground. This is called bench-grafting [6].
To perform whip grafting:
- Cut a scion about 10-20 cm in length from a healthy tree with desirable traits.
- Cut off the tip and base of the scion to remove any weak or flower buds.
- Using a sharp knife or a grafting tool, make a sloping cut about 2.5-3 cm long at one end of the scion.
- Make another slice through the middle of the cut end to create a tongue.
- Cut off a rootstock about 20-30 cm from the ground or from the pot.
- Make a similar sloping cut and a tongue at the cut end of the rootstock.
- Fit the scion and rootstock together so that the tongues interlock and the cambium layers align.
- Wrap the graft with grafting tape or rubber bands to secure it and prevent it from drying out.
- Cover the graft with grafting wax or paint to seal it and protect it from infection.
- Prune back the scion to just two or three buds to reduce water loss and encourage growth.
Cleft Grafting
Cleft grafting is another common method of grafting fruit trees. It is suitable for scions that are smaller than the rootstocks and have diameters of less than 1/4 inch (6.35 mm). Cleft grafting is often done outdoors on established trees that need to be changed or improved [7].
To perform cleft grafting:
- Cut a scion about 10-15 cm in length from a healthy tree with desirable traits.
- Cut off the tip and base of the scion to remove any weak or flower buds.
- Using a sharp knife or a grafting tool, make a wedge-shaped cut at one end of the scion.
- Cut off a branch or a trunk of a rootstock about 2.5-5 cm in diameter and 30-60 cm from the ground.
- Using a grafting knife or a chisel, split the cut end of the rootstock about 5 cm deep to create a cleft.
- Insert the scion into the cleft so that the cambium layers align. You can insert two scions on opposite sides of the cleft for better chances of success.
- Wrap the graft with grafting tape or rubber bands to secure it and prevent it from drying out.
- Cover the graft with grafting wax or paint to seal it and protect it from infection.
- Prune back the scion to just two or three buds to reduce water loss and encourage growth.
Bark Grafting
Bark grafting is another method of grafting fruit trees. It is suitable for scions that are smaller than the rootstocks and have diameters of less than 1/4 inch (6.35 mm). Bark grafting is often done outdoors on large trees that have been damaged by frost, fire, or pruning [8].
To perform bark grafting:
- Cut a scion about 10-15 cm in length from a healthy tree with desirable traits.
- Cut off the tip and base of the scion to remove any weak or flower buds.
- Using a sharp knife or a grafting tool, make a wedge-shaped cut at one end of the scion.
- Cut off a branch or a trunk of a rootstock about 5-10 cm in diameter and 30-60 cm from the ground.
- Using a grafting knife, make a vertical slit about 2.5 cm long through the bark of the rootstock, but not into the wood.
- Peel back the bark slightly to create an opening for the scion.
- Insert the scion into the opening so that the cambium layers align. You can insert several scions around the circumference of the rootstock for better chances of success.
- Wrap the graft with grafting tape or rubber bands to secure it and prevent it from drying out.
- Cover the graft with grafting wax or paint to seal it and protect it from infection.
- Prune back the scion to just two or three buds to reduce water loss and encourage growth.
Bud Grafting
Bud grafting is another method of grafting fruit trees. It is suitable for scions that are only one bud long and have diameters of less than 1/4 inch (6.35 mm). Bud grafting is often done outdoors in late summer when the bark of the rootstock is easy to peel.
To perform bud grafting:
- Cut a scion about 10 cm in length from a healthy tree with desirable traits.
- Cut off any leaves from the scion, but leave their petioles attached as handles for later use.
- Using a sharp knife or a budding knife, cut out a bud along with a thin slice of wood and bark from the scion. This is called a bud shield.
- Cut off a branch or a trunk of a rootstock about 2.5 cm in diameter and 30-60 cm from the ground.
- Using a budding knife, make an inverted T-shaped cut through the bark of the rootstock, but not into the wood.
- Peel back the bark slightly to create an opening for the bud shield.
- Insert the bud shield into the opening so that its cambium layer aligns with that of the rootstock. The bud should face upward and outward.
- Wrap the graft with budding tape or rubber bands to secure it and prevent it from drying out. Leave only the bud exposed.
- Cover the graft with budding wax or paint to seal it and protect it from infection.
How to Care for Grafted Fruit Trees
After grafting, you need to take good care of your grafted fruit trees to ensure their survival and growth. Here are some tips on how to care for grafted fruit trees:
- Water the grafted trees regularly, especially during dry periods. Avoid overwatering or underwatering, as both can cause stress and reduce graft success.
- Fertilize the grafted trees with a balanced fertilizer, such as 10-10-10, after they start growing. Follow the label instructions and do not overfertilize, as this can cause excessive growth and weaken the graft union.
- Prune the grafted trees to remove any unwanted shoots or branches that may compete with the scion. Prune also to shape the tree and improve its structure and appearance.
- Protect the grafted trees from pests and diseases by applying appropriate pesticides or fungicides when needed. Follow the label instructions and use only products that are safe for fruit trees. Monitor the grafted trees for any signs of infection or infestation and treat them promptly.
- Remove the grafting tape or rubber bands after the graft has healed, usually in a few weeks to months. Do not remove them too early or too late, as this can damage the graft union or cause girdling.
- Remove the budding tape or rubber bands after the bud has sprouted, usually in a few weeks to months. Cut off the top of the rootstock above the bud to allow the bud to grow into a new branch.
Conclusion
To conclude, grafting fruit trees is a useful and enjoyable skill that can help you create your own custom fruit trees. By following the steps and tips in this article, you can successfully graft different varieties of fruit trees and enjoy their fruits for years to come. Grafting can also help you repair damaged trees, improve tree health and productivity, and propagate rare or heirloom cultivars. Grafting is not difficult, but it requires some practice and patience. With some basic tools and materials, you can start grafting fruit trees today and have fun with this rewarding hobby.
Frequently Asked Questions
- Why graft fruit trees? Grafting fruit trees can have many benefits, such as:
- Creating new fruit varieties by combining the best traits of two different plants
- Repairing damaged or diseased trees by replacing their tops with healthy ones
- Improving tree health and productivity by using rootstocks that are more resistant to pests, diseases, drought, or soil conditions
- Propagating rare or heirloom cultivars that are difficult to grow from seeds or cuttings
- Saving space and increasing diversity by growing multiple fruit varieties on one tree
- What fruit trees can be grafted? Most fruit trees can be grafted, as long as they belong to the same species or genus. For example, you can graft different varieties of apples, pears, plums, peaches, cherries, apricots, citrus, etc. However, some fruit trees are more difficult to graft than others, such as figs, persimmons, olives, avocados, etc. You can also graft some fruit trees that are closely related but not in the same genus, such as peaches and plums, apples and quinces, pears and loquats, etc. However, these grafts may not be very stable or productive.
- When is the best time to graft fruit trees? The best time to graft fruit trees is late winter or early spring, before the buds begin to swell. This is when the plants are dormant and have stored enough energy for growth. This is also when the cambium layer is active and can form a strong union between the scion and rootstock. However, some methods of grafting can be done at other times of the year, such as bud grafting in late summer or bark grafting in early summer.
- How long does it take for a graft to heal? The healing time of a graft depends on several factors, such as the type of graft, the type of plants, the growing conditions, and the care given. Generally, it takes several weeks to months for a graft to heal and form a strong union between the scion and rootstock. During this time, you need to keep the graft moist and protected from drying out or infection. You also need to monitor the growth of the scion and rootstock and prune any unwanted shoots or branches.
- How do I know if a graft is successful? You can tell if a graft is successful by observing its appearance and behavior. A successful graft will show signs of growth and vitality, such as:
- The scion will produce new leaves and shoots
- The scion will produce flowers and fruits (depending on the variety and age)
- The scion will have a healthy color and texture
- The scion will have a smooth transition with the rootstock
- The scion will have a firm attachment with the rootstock A failed graft will show signs of decline and death, such as:
- The scion will wilt and dry up
- The scion will turn brown or black
- The scion will have a rough or cracked transition with the rootstock
- The scion will have a loose or detached connection with the rootstock
