A graft can be a bit complicated to explain because, let's say, it's better understood if you see it. It's one of those activities that makes more sense in practice. However, we will try to pass on this wisdom, straight from the field, using images and words. Luckily, we have Eduardo, farmer and founder of Campos del Abuelo, to help us better understand what a graft is and what it's for.
Trees have always been grafted...
Grafting has existed since humans were nomads. Since men and women traveled from one place to another, looking for food and transporting seeds. It happened that sometimes, even if the seed was transported from one place to another intact and then planted, a different plant was born from the mother tree it came from...
Our species paid attention to this permanent movement. Thus, it realized that there were plants that fused with each other naturally. Some joined through their branches, others from their roots.
From there, humans copied this gesture from nature to grow plants with certain characteristics, taking into account the quality, size, or flavor of the fruit. Citrus trees, for example, must be grafted to produce fruits of a certain variety.
In China, at the beginning of the first millennium BC, there are records of this plant propagation technique being used. Aristotle mentions grafts in his writings, and they are also associated with the Greeks and Romans.
This technique has advanced at the same pace as humans. To this day, it continues to be used in cultivation fields, and for farmers, grafting varieties is natural.
Through this article, we will explore this ancient technique to learn: what grafts are, how to make one, the tools needed, and the types that exist.
What is a graft?
Eduardo explains it in a very simple way: A graft is a small piece of trunk from one variety that is placed on another tree, to change its variety to that of the first. The purpose of grafting is simply to change the variety of a tree that has a type of fruit that, for whatever reason, we are not interested in having, and replace it with another.
That is, grafts are methods of vegetative propagation. What is done is to manually join one plant with another so that they grow together as a single plant, as a single organism.
To make a graft, we have two different plant parts. On one hand, the tree without a variety, to which we will add a piece of the plant that contains the variety. This tree is known by several names: rootstock, understock, or stock.
Cherry trees are another type of fruit tree that need to be grafted to bear fruit of a certain variety.
On the other hand, we have the plant that contains a variety. From this, we will take a branch or a piece of bark to join to the rootstock tree. This plant is the one that will provide us with fruit with certain characteristics, as the farmer explained to us.
Once the two parts begin to fuse, the rootstock tree provides the grafted branch with nutrients to survive until they eventually transform into a single organism.
What is grafting for?
From a technical perspective, when we join one plant to another, nature provides us with several benefits. By grafting, we achieve the propagation of species in a simple way, and new species can also be created. For example, the Hass avocado variety was born from a graft of a rootstock tree with two other varieties. And since we mentioned avocado, in this article about Bacon avocado, Salvador, the farmer who grows them, explains avocado grafts very well.
Returning to the topic. Another benefit is that the rootstock tree can provide the grafted variety with the possibility of surviving in a certain environment where it might not survive alone. Similarly, the grafted variety can also provide strength to the rootstock tree. Either way, it serves both.
In the field, where we constantly have to adapt to the needs of the market and our customers, grafting gives us the possibility to change varieties. A single tree can be grafted with different varieties from one season to another.
Like any ancient technique, it must be performed with knowledge to yield results...
Conditions for grafting
To make a successful graft, meaning it takes and produces quality fruit, certain important points must be taken into account:
- The scion and rootstock must be compatible, Eduardo explains this very well: All trees can be grafted. However, it is important to note that certain varieties cannot be grafted onto different trees or rootstocks, meaning, you cannot graft citrus fruits onto a plum tree. So within the citrus family, all varieties can be exchanged: oranges, lemons, and grapefruits all have the same family of rootstocks and trunks, and they do allow for variety changes. But not between citrus and stone fruit, for example. They must be of the same family.
- Both trees, both the rootstock and the one containing the variety, must come from healthy plants; this is important so they are strong and can form the union.
- Grafting should be done at the appropriate time. Eduardo tells us that although it can be done at any time of the year, there are two times when it is best: The best time to graft, coincides with spring, which is in the months of April and May, and in September and October. During these months, the trees somehow sprout and have more sap.
Types of grafts
There are different ways to graft, as we mentioned at the beginning, it is a very old technique. But like everything, it changes and adapts to new times... Eduardo tells us about it:
Grafting techniques vary. In the past, two were used: the chip bud and the shield bud. But over time, new grafting techniques have emerged.
Before, the tree was prepared by cutting certain branches below and leaving only a part of the wood clear to be grafted.
However, new techniques have emerged, and what is done now is that the tree is completely cut down. Only the trunk is left, and a stake of another variety is inserted and, apparently, it gives good results because that graft grows faster without the competition from higher branches.
Grafting tools
Grafting is a manual technique, but to perform it precisely, some tools are also needed. In Eduardo's case, he uses the following:
Depending on the type of graft, it can be either a chainsaw, as cutting the entire tree is done with a chainsaw. Otherwise, grafting knives are used, which is a half-moon shaped tool used to make cuts in the wood and insert the graft.
Sometimes he also uses a knife or a pair of scissors, as we see in the image. It is very important that the tools are disinfected. What we recommend from the field is to disinfect with alcohol just before starting work.
How to make a graft?
As our experienced farmer explains, to carry out a graft, first, the tree must be prepared. Eduardo gives us an example:
If we were to do a classic graft, we would cut certain branches below and leave a part of the trunk clear. Then we would let the tree recover its sap because when you cut branches from the tree, the sap stops circulating. Let's say it gets scared and stops, but after a few days, it recovers its sap and then you proceed to graft.
We're going to give another example because we know this grafting thing isn't easy to understand. Let's look at a type of graft called T-budding or shield budding.
It's called that because a T-shaped cut is made on the tree to be grafted. And once done, the chip (that is, the small green piece of branch) containing the variety is placed inside. You'll see it more clearly in the images, let's go step by step.
Step 1: you have to make a cut in the brown part of the trunk. Incisions are made and the white part is accessed, which is where the graft is placed.
Look, in this image you can see how the T-shaped cut is made:
Step 2: Once we make the cut, we are going to lift that part of the bark to reach the white part:
Step 3: we take the branch to be grafted. It is cut from the tree of the desired variety, only the green part is removed. Special attention must be paid to this: not the whole branch, but only the green part. And we make the cut.
That chip we removed from the branch, is what we will place on the white part of the tree we are going to graft.
Step 4: once the bud is placed on the rootstock tree, a plastic strip is wrapped around it. Before, it was done with esparto, which was much more expensive because the esparto had to be prepared, but now plastic strip is used and placed like this:
Step 5: it is important to wrap the graft tightly with plastic strips so that air does not enter and it can dry out; only the bud of the graft is left exposed, and the rest is carefully covered and tied.
Then, as Eduardo says, it's a matter of waiting.
After about 20 days we can examine the graft, if the chip is still green, then the plastic is removed because it has already adhered to the trunk where we placed it.
And from there, if all goes well, in a few days it will begin to sprout from the new bud. From this new sprout that the tree has, the new variety is generated. In turn, as it grows, the branches of the previous variety are cut and the new ones are allowed to grow until the tree is covered by the new variety.
Sounds incredible, doesn't it? From the graft, the rootstock tree and the grafted bud become a single unit, a single tree that will bear new fruits.
We hope this information is new to you; if you have any questions, don't hesitate to ask us. Remember to visit our online fruit and vegetable store. You can customize your box with the products you want and receive it at your home directly from the farm.
Until next time and thanks for reading!
Bienvenida- welcome
