Grafting a pecan tree is a great way to produce a high-quality nut-bearing variety with the added hardiness of a local rootstock. This is a win-win situation; cold-hardy rootstock that doesn’t make the best nuts, can be teamed up with a champion nut-producing cultivar. Here we will discover how to graft a pecan tree to achieve this.
What You'll Learn Today
When Should You Graft A Pecan Tree?
Pecan trees should be grafted in the spring before they begin growing. In the United States, this is between February and early April, depending on the location and cultivar.
Collect your graft wood (scions) from late December to January. To prevent the need for long storage, collect your scions as short a time as possible before you intend to graft them.
How Is A Pecan Tree Grafted?
To begin, let’s look at the terms used when grafting a tree and what they mean:
- Scion – This is the name of a dormant shoot you cut from the parent tree to join it to the rootstock. This creates a clone of the parent tree. Scions are usually taken from the previous season’s growth. A scion can also be called graftwood.
- Rootstock – This is the tree you are going to use as the root for the scion to be attached to. Rootstock can refer to a cut back seedling which is little more than a root with a small amount of leader (trunk) remaining. It can also be the limb of a larger tree. Rootstock can also be called Understock.
- Cambium – This is a layer of cells between the bark and the wood of a tree. The cambium forms the growing part that produces new bark and new wood each year. Hormones, called auxins, pass to it, stimulating cell growth.
- Grafting – This is the process by which a scion is joined to the rootstock to form a new tree. The tree will take on the characteristics of the scion’s parent tree.
- Topworking – This is where the top of a tree is replaced with a graft from the desired cultivar.
There are various methods used to create grafted trees. In this article, we are going to look at two of the simplest ways to graft a tree, suitable for beginners. We will look at “Whip Grafting” and “Four Flap (Banana) Grafting”.
Before you can graft a tree, first, you need some rootstock. There are a few ways to do this. Firstly, and by far the quickest way, is to find some self-sown seedlings in a pecan grove, dig them up and transplant them to where you wish to grow your pecan tree. Always ensure you have permission from the landowner!
The second way is to grow some pecan trees from nuts grown in your local area. The reason for using local seeds is because the trees are used to your climate, so the rootstock they produce will also be happy where you live.
Seedlings grown from nuts will need to be two years old before they are mature enough to use as rootstock.
The last way is to take some spring cuttings from the newly sprouted growth of local trees and try to root them. If the cuttings take, you will be able to use them as rootstock the following year.
See our article “How to Grow a Pecan Tree” for complete information on growing rootstock from seed or cuttings.
Collecting and Storing Scions (Graftwood)
Once you’ve gathered your scions when they are dormant in December or January, you need to store them safely until you’re ready to start grafting.
If scions are not stored correctly, your grafting attempts will fail.
Care must be taken to ensure your graftwood is free from disease and insect damage, is not allowed to freeze, is of the right age, and has only mature buds.
Age of Scions
Scions should be cut from previous season growth. Look for smooth, straight ones with healthy-looking buds and a quarter to five-eighths of an inch in diameter.
Cut lengths of six to eight inches, ensuring there’s no sign of disease or insect damage.
Don’t use the end sections, as the buds will be immature. Use a section from lower down and cut it off where it gets to three eighth of an inch in diameter, and the bark hasn’t got a pithy appearance.
If you’re going to use whip grafting techniques, use freshly cut scions immediately; there’s no need for storage. If you want to try the 4-flap method, then you’ll need to cut your scions when the tree is dormant between December and January.
Place your scions into old bread bags or plastic garbage sacks packed with damp cedar shavings. Ensure the scion is entirely covered by the shavings.
The cedar shavings will prevent pathogenic fungi from developing and keep the cut wood from drying out.
Label each bundle clearly, showing which pecan tree cultivar they contain, unless you use only one type.
Store scions in this way for a maximum of six months. Ideally, keep the temperature between 36°F and 38°F.
How to Whip Graft a Pecan Tree
Whip grafting is a straightforward technique and avoids the need to store scions. Freshly cut ones may be used immediately.
- In February, find appropriate rootstock seedlings. They should be two years of age and approximately three-eighths of an inch in diameter.
- Select your scions from the tree you wish to use as a parent. Remember that your grafted pecans will take on the same traits as their parent tree.
- You will be grafting the scion whips to the rootstock approximately two inches above soil level. Although you can also do this below soil level, you’ll need to remove the soil from around the graft later, or this will cause problems as the tree grows.
- If you use an older tree as rootstock, you can graft a whip to one of the tree’s limbs. Choose a branch of around the same diameter as the scion you’ll be using to make the graft. De-horn the limb to allow for the development of new growth.
- As described above, select scions from one-year-old wood from the parent tree. For seedling rootstock, the scions should be seven to ten inches in length. For older trees, they can be four to six inches long.
- On the rootstock, use a small, sharp-bladed knife to cut off the wood above the graft site at a 45° angle. The cut must be precise and clean with no jagged edges.
- Now make a 45° angle cut on the scion.
- Next, you need to make a tongue and groove so that the two cut planes from each component piece lock together. To do this, cut a vertical groove, half to three-quarters of an inch deep in the center in the rootstock, straight through the 45° cut you made earlier. Now mirror this groove in the scion by creating a tongue that will fit into it. To do this, cut to just under halfway across the scion, following the same 45° angle, at a distance equal to the groove you made in the rootstock, and then cut from the other side to leave a tongue.
- Carefully insert the tongue of the scion into the groove of the rootstock so that the 45° cut angles face each other, giving you an upright branch.
- Wrap some grafting tape around the joint and wrap the entire graft in parafilm.
Four Flap (Banana) Grafting
Another grafting style that is simple for a novice to master is the “four flap” or “Banana” graft.
It’s essential for the success of this graft that the scion and rootstock are a very similar size. If there is a discrepancy, the scion should be very slightly larger than the rootstock.
The reason four flap grafting is both easy and successful is that it allows an excellent connection between the rootstock and the scion. There are eight places where cambium can connect between the two sections within the graft. This means precision cuts are less critical than with other graft types.
Scions should be collected in late winter while the wood is dormant and stored as described earlier.
Four flap grafts can be used on young rootstock or on older tree limbs, providing they are under one inch in diameter and have been dehorned.
The four-flap method is employed later than whip grafts and should be done in April or May.
- First, decide where on your rootstock you want to make the graft. Unlike whip grafts which need joining low down, four flap grafts can be higher, and it’s easier to do them at a comfortable working height.
- Begin by removing all lateral growth below the point you wish to make your graft.
- Make a horizontal cut straight across your rootstock, ensuring it’s clean and precise. Do this with a pair of sharp pruning shears.
- Place two rubber bands around the rootstock at three to four inches under the cut you made. Ensure they are snug and not too loose. You will need them to close your graft later.
- Using a very sharp, small bladed knife, make a cut straight down through the flat surface you’ve just cut right in the center. The cut should be approximately three-quarters of an inch in depth.
- Now make a second cut straight across the first to the same depth. You should have a perfect X through the center of the cut surface of your rootstock.
- Find a smooth, straight scion the same diameter or very slightly larger than your rootstock. Ensure there are several healthy-looking buds on the scion.
- Again, using your sharp knife, partially remove two inches of the bark from the scion on four sides. Leave a slender strip of bark between each of the strips you remove. This is important for the success of your graft!
- Square off the last quarter-inch of the scion so that it tapers in slightly. Do this by making your cuts marginally deeper towards the end. Make sure the bottom is flat and square when you’ve finished.
- Going back to the rootstock, use your knife to help you pull down four flaps of bark as if you were peeling a banana (hence the name banana graft). You want to expose approximately two and a quarter to two and a half inches of bare wood.
- Now with your sharp loppers, being careful not to damage your bark flaps, cleanly cut off the piece of bare wood that is sticking up. Make sure you leave a flat surface.
- Place the scion on top of the rootstock and pull up the four flaps so that the small sections of bark you left on the scion fill any gaps between each flap.
- Push your first rubber band up to the top of your flaps to hold them in place and the second rubber band halfway up for additional support.
- Wrap the entire graft in Parafilm strips sealing all of the cuts. Parafilm is breathable and prevents excess moisture buildup while preventing the graft from drying out.
- If the graft is successful, it will start growing in the next four weeks.
In this video, you will see how to graft a pecan tree cutting onto rootstock to grow your own clone pecan tree:
What Rootstock Is Used For Grafting Pecans?
The hickory tree is a close relative to the pecan, and some use it as rootstock for a grafted pecan tree.
In truth, this is not a good match. The hickory wood is slow growing, while pecan is fast. This causes stress on the tree as it tries to grow.
Grafting hickory onto pecan rootstock is less of a problem, but the reverse really should be avoided.
You can use any pecan seedling as rootstock for your desired cultivar. Always use rootstock that grows well in your location, as this is part of the beauty of grafting trees. By using a hardy rootstock, you can graft more fragile varieties onto them.
Popular varieties for grafting include “Moreland” and “Cape Fear” as they produce a good quality nut and are relatively easy to graft. If someone you know has a pecan tree that produces good nuts, then there’s no reason why you shouldn’t have a go at grafting it, provided they have no objections to you taking some cuttings.
Although you can grow pecan trees from nuts, you won’t know if the nuts it produces are any good until it matures. That means a long wait of 10 years or more.
A far more reliable method is grafting a cultivar with the properties you desire onto some hardy rootstock.
The rootstock can be a two-year-old seedling pecan tree you’ve grown yourself. Alternatively, transplant a one-year-old seedling from a pecan grove on your land, or buy a suitable seedling from a nursery.
The last alternative is to use a branch from an existing pecan tree.
There are various graft types, but we have described how to achieve two of the easier ones in this article. It’s worth trying out several different styles and seeing which works best for you.
For more blogs and articles about all kinds of great topics, including more on pecans, visit our blog.