Apple rootstock is one of the most important elements in planning your apple orchard.
The size of your apple tree, the number of years you wait for fruit, and your yield depend solely on the rootstock variety.
There are widely different varieties of apple rootstock out there, so let’s dive into everything you need to know.
What is a Rootstock?
The rootstock consists of the root portion of a tree that has been grafted onto what’s known as the scionwood. The scionwood determines the variety of apples and contains the DNA for everything above the graft at the base of the tree.
This allows you to get the best traits of both the rootstock and the scionwood that were grafted together.
For more information on what grafting is and how to graft a tree yourself, read our in-depth How to Graft an Apple Tree Complete Guide.
Researchers have bred specific kinds of rootstock for many years in order to get the trees to produce what they want.
Rootstock is not only important for apple trees. They are just as influential for other fruit trees as well, like pears.
History of the Apple Rootstock
Most of the apple rootstock we use today has been continuously developed since the 20th century.
Dr. Ronald Hatton of England’s East Malling Station began working on creating different kinds of rootstocks for different purposes. Specifically, he created many dwarf rootstocks that resulted in easier trees to pick for commercial use.
Hatton ended up creating 24 different varieties of apple rootstock. In 1917, a collaboration between Hatton’s Malling Station and the John Innes Institute at Merton Park saw the creation of the famous MM series of rootstock.
MM rootstock’s main purpose was disease resistance development. Specifically, it is resistant to a disease known as wooly apple aphid.
All rootstock varieties were developed to be resistant to even more diseases in the 1960s, and those are the ones we mainly use to this day.
The Importance of Apple Rootstock
The rootstock you use influences the size, vigor, disease resistance and other factors for the tree. Various apple tree rootstock can produce anything from dwarf trees that are easy to pick to vigorous trees that produce more yield but are much larger and harder to pick.
Rootstock is selected based on the various sizes and trait they offer.
As with all kinds of plants and trees out there, apple trees and their rootstocks are susceptible to a wide range of diseases.
Among those diseases are anthracnose canker, bull’s-eye rot, apple scab, armillaria root rot, phytophthora crown rot, collar rot, root rot, and powdery mildew.
That’s a lot of potential diseases your tree can get. Not to worry though, these diseases can be prevented as long as you’re careful.
Hygiene is essential, and sterilizing pruning sheers before cutting with 70-90 percent alcohol is a great way to ensure that your equipment won’t contaminate any of the apple trees or your other plants as well.
Making sure there is proper drainage is also a crucial aspect of avoiding disease. Flooding or too much moisture, in general, can lead to root rot and many of the other diseases listed above.
Before getting to the sizes of the trees, let’s take a look at what controls the size in the first place, the apple tree rootstock.
Developed by Dr. Ronald Hatton and the East Malling research station in England more than a century ago, this is the most well-known producer of rootstock.
They have a rootstock for every tree size you can think of. The downside is that they’re less disease-resistant than some of the others on this list.
A collaboration between the East Malling research station and the John Innes Institute at Merton Park, the apple rootstock created from this combined effort is for disease resistance.
There is way more MM rootstock than there is Malling rootstock.
Malling and Merton-Malling rootstocks are usually referred to M and MM respectively. However, sometimes they’re referred to as EMLA rootstocks. EMLA is specifically used when referring to the virus-free derivatives of M and MM rootstock.
Hailing from Brazil, this program’s rootstock is on the cutting edge of science having almost exact control over size and disease resistance.
The Geneva Program was started by Cornell University to create many different varieties of apple rootstock that could meet every need an apple tree grower could possibly have.
Starting as open-pollinated rootstock hybrids, Vineland is new on the scene. This rootstock was created in the Horticultural Experiment Station in Vineland, Ontario, Canada.
They are known for being cold hardy and are also very disease resistant.
Developed in the former Soviet Union at Michurinsk College in the 1960s, these rootstocks are known for their cold hardiness. They are commonly referred to as Bud or B rootstocks.
Bud rootstocks were the first rootstocks to be developed after the Malling rootstocks.
Size Groups of Apple Rootstocks
There are 4 different sizes of trees that an apple rootstock can produce. The sizes are dwarf, semi-dwarf, semi-vigorous, and vigorous. Each has different traits that alter the plant drastically from one another.
With that being said, let’s get into more detail about each different size your apple rootstock can provide.
Dwarf trees are meant for easy fruit picking. Their small size makes them ideal for any home garden since they take up less space. They are also easy to move in case you want to re-organize your garden.
They are also easier to care for due to their size. The fact that they are smaller than your average apple tree means it’s easier to evaluate and handle anything that happens in any spot of the tree.
The drawback is that its smaller size means a lesser yield. The yield of a vigorous apple tree could be anywhere from 3 to 4 times more than a dwarf. Still, if you’re just trying to have enough apples for your family, a few dwarf trees (remember you need a pollinator!) should be more than enough.
Dwarf trees also have shorter life spans than the other sizes on this list. Dwarf trees do have a long life of 15-20 years, but vigorous trees live anywhere from 30-45 years.
Let’s get into the most popular types of dwarf apple tree rootstock you can buy.
A virus-free clone of the M9, this rootstock will produce a reliable tree. The EMLA 9 is known for being resistant to collar rot.
This rootstock’s tree will grow to about 40 percent of the size of a full-grown tree, which is on the size limit for dwarf trees.
The Geneva 11 is a hybrid rootstock created by the Cornell University breeding program. It’s known for being resistant to fire blight which is quite rare.
The tree produces more yield than M9 rootstock and is a great addition to any garden where fire blight is prone to happen.
Geneva 41 is similar to the 11 in its fire blight resistance, but it also has the added resistance to Phytophthora. It’s known for making a tree that will produce nicely sized fruits with very little issue.
The only problem with it is the quality of the roots, as sometimes they can produce side shoots or just not entrench themselves in the soil properly.
Another Geneva variety in this section, this rootstock is probably the best all-around choice thanks to the many diseases it’s resistant to.
The Geneva 214 is fire blight, wooly apple aphids, replant disease, and root rot. It also produces one of the highest yields of any dwarf tree. The tree that comes from this rootstock is a great worry-free choice.
As with all Budagovski rootstocks, the 9 has amazing winter hardiness. This particular rootstock is also very resistant to collar rot.
This rootstock will produce a versatile tree that’ll start yielding fruit early and can do well in just about any orchard or garden you can think of.
The Malling 27 rootstock is great for home gardens. Known for its compact size and is sometimes referred to as “super dwarfing” because at full size it’ll stand from 3 to 5 feet tall. It will produce fruits after just 2 years.
They require more attention than some of the other kinds of rootstock that will appear on this list, but relatively speaking it requires the same amount of care as any fruit or vegetable plant.
The Vineland 3 apple tree rootstock was created by Vineland Farms in the 90s. It’s a favorite of farmers because of its cold weather hardiness.
This tree grows to around 5-6 feet at full maturity and produces gorgeous white and pink blossoms in spring.
The Geneva 65 rootstock is similar to the M27 in size and the time it takes to fruit. However, this variety is known for its great disease resistance. Specifically, it’s more resistant to collar rot than other kinds of apple rootstock.
A semi-dwarf apple tree is a great option if you have more space in your home garden and need a higher yield than what a dwarf tree can provide.
These trees usually grow from 12 to 15 feet and produce at least twice the yield of a dwarf tree. Since they are quite a bit larger than dwarf trees, they are also a great source of shade in the summer!
Its size is still what would be considered “easy” in terms of care and picking, but you do have to use a ladder to reach the top of the tree if necessary.
Let’s dive into what the most popular varieties of semi-dwarf apple tree rootstock are and what they offer.
A cross between the M9 and M16 rootstocks, this virus-free rootstock created by East Malling is a great addition to any orchard. The EMLA 26 grows to about 45 percent of the size of a full-grown apple tree
The tree is known for producing better quality yield than other trees normally do early in its life, after which it levels out of course. Even though it’s virus-free, the plant is not resistant to some diseases like collar rot.
Resistant to crown rot and fire blight, this rootstock carries Geneva’s signature disease resistance well.
The resulting tree can grow one foot larger than the range we have for the semi-dwarf trees, but for the most part, should stay within the range while producing a suitable yield for the size.
The Geneva 890 produces a tree that’s an absolute wonder of disease resistance. The tree will be resistant to fire blight, crown rot, and wooly apple aphid. Needless to say, the list of worries you’ll have with this tree will be significantly less burdensome than most.
This rootstock can also vary in size depending on the conditions, but overall it’ll for anywhere from 50 to 65 percent of the size of a full apple tree
The Geneva 202 is the ideal replacement for the M or EMLA 26 rootstocks in environments where trees are susceptible to wooly apple aphids thanks to its hardy resistance to the disease.
The only downside is that the resulting tree will produce less yield than its other Geneva counterparts.
The Malling 7 is the ol’ reliable of all semi-dwarf rootstock. It’s the standard for which a semi-dwarf apple tree rootstock is gauged. It is essential for the soil to be perfect for the tree this rootstock produces as it anchors poorly and can lean.
It’s resistant to collar, crown, and root rot and is incredibly resistant to fire blight.
The Geneva 935 is a rootstock that has an amazing combination of excellent fruit production and disease resistance.
This combination is rare among apple trees and makes this an incredibly versatile option
The Merton-Malling 106 is known for its reduced drought sensitivity. As a result of this, this apple rootstock doesn’t need the best soil in order to thrive, unlike the M7.
The Supporter 4 is from a different background than all the rootstocks here, but it had to be added to this list as it’s a great option. Produced by the Pillintz Research Station in Germany, the world wasn’t introduced to it until after the fall of the Berlin Wall.
It is known for its excellent yield production and adaptability to low-vigor style orchards.
The semi-vigorous is your almost full-sized apple tree. They grow anywhere from 16-22 feet tall.
They take longer to produce their yield than dwarf trees, but when they do finally produce their yield they produce significantly more than any of the dwarf family of apple rootstock.
While having more yield is lovely news, the tree is harder to take care of due to its size.
With that being said, let’s explore the most popular varieties of semi-vigorous apple tree rootstock
The Merton-Malling 111 tree is about 80 percent of the size of a full-size apple tree. Considered to be one of the best apple rootstock available, this variety is virus-free and very disease resistant.
It’s a rootstock that’ll produce an all-around tree that has everything you can possibly ask for. Disease resistance, good yields, good anchorage to the soil, and a great spot to have a nice shaded picnic with the family.
The Malling 106 rootstock produces a tree that is 15 feet plus tall. This one is known for its exceptionally high yield given its size.
This tree is the ideal tree if you have a large space to plant your tree in as it takes up a lot of room. They also require very little attention unless there is a drought.
A rootstock that is could reach up to 95 percent of a full-sized apple tree, the Budagovski 118 was made to survive harsher conditions and produce large yields.
This incredible cold-hardy rootstock is a cross between M8, M9, and a Moscow Pear scion. Due to this mix, it can survive in sandy low-quality soil. If you live in a place where the weather and environment aren’t so kind, this is your go-to rootstock.
The vigorous apple tree is the original and full-sized apple tree. These trees grow to 20 feet plus and produce by far the largest yield of any of the types listed here.
A full-size vigorous tree is also what you’ll get if you plant an apple seed directly – but you won’t know what variety of apple or rootstock you’re getting – and that’s why it’s not recommended!
Vigorous trees take longer to crop than even semi-vigorous trees, but this comes with the largest yield and the longest life span.
The vigorous apple tree is also the one that requires the least maintenance of all the apple trees. This is because this is full-sized and nothing is altered for it. It’s the tree that has survived for millennia on earth.
The Malling 25 is the only rootstock to produce a vigorous tree, this is the one you want if you want the original apple tree.
The tree produces the largest yield and is the best apple tree for surviving in bad soil. You will need a ladder to pick the apples, but you’ll have more apples than you know what to do with.
What Should You Select?
The first thing you should consider is the size of your garden. You shouldn’t have a vigorous tree growing in a small house garden. Get a size that will have enough room to grow peacefully.
Yield is also an important factor to consider. If you are just trying to have enough apples for your family for example, then a dwarf is all you need.
Lastly, you should consider how much time you have to maintain the tree and how able you are to care for the tree should it get a disease.
Buying Your Apple Tree
Now that you’re armed with knowledge about the different apple tree rootstocks, it’s time to shop for an apple tree that will be just right for your orchard.
You’ll love the selection available at one of our favorite retailers, Stark Brothers. There’s sure to be an apple tree that works for your garden!
The All-Important Apple Tree Rootstock
No matter what kind of apple tree you want, the first thing to consider is what kind of rootstock you want. The rootstock sets the tone for everything else that follows as you’re growing your apple tree
If you want more information about apples, take a look at our Apple Trees page on our website. You’ll find blog posts on more than 90 apple varieties, plus our extensive collection of comprehensive growing and care guides.