Most fruit trees available for purchase in nurseries, large hardware chains and online stores are grafted. This means that the desired tree has been added onto a rootstock, that can alter the growth habits of the tree.
For example, a small branch called a scion can be taken from a Granny Smith apple tree and can be grafted onto the roots of a different apple variety to dwarf the size of the Granny Smith tree to under 2 metres. Without being grafted onto dwarfing rootstocks, a Granny Smith apple tree grown from seed will grow to over 9 metres tall.
What is a rootstock?
A rootstock is the root system of a grafted tree. These rootstock trees are grown for one year, before a piece of scion (a small branch from the tree with the desired fruit qualities) is grafted onto the trunk of the rootstock. Once established, any remaining branches and foliage from the rootstock are removed so that only leaves from the scion are allowed to grow.
Often, if rootstocks are allowed to grow into full sized trees without scion grafted on top, they will bear poor quality fruit (if they fruit at all). However, the tree will probably be very hardy, and have good disease resistance
We can use different rootstocks to control the following attributes of fruit trees:
- Tree size (or vigour)
- Time to fruiting (from the standard 7+ years, to as little as 2 years)
- The ability of the plant to survive in certain soil types or climatic conditions
- The ability to tolerate wet (or very dry) soils
- Disease resistance
- Stability of the plant and ability to withstand strong winds
- Hardiness of the plant
Generally speaking, the qualities of the fruit, such as taste, texture, colour and timing of ripening are determined by the scion.
By grafting fruit trees with the right combinations of rootstocks and scions we can have hardy, disease resistant trees that produce large quantities of tasty, quality fruit.
Don’t pick a fruit tree to plant into your garden based only on the type of fruit it will bear. Make sure you pay attention to the rootstock , as this controls many of the attributes of the fruit tree.
Dwarf fruit tree rootstocks
The development of dwarfing rootstocks for many different fruit trees, means that we can now grow very productive trees in much smaller spaces. There are many different dwarf rootstocks and they all dwarf trees to various degrees.
Fruit trees grafted onto dwarf rootstocks have many advantages over standard sized trees:
- They keep the fruit trees very small, so they can be grown in small spaces, espaliered along driveways, on balconies and grown in large containers
- They hardly (if ever) require pruning because they don’t keep trying to grow into a 10 metre high fruit tree,
- They often fruit within 2 years instead of the usual 7 to 10 years.
- You don’t need a ladder to pick the fruit
- Netting to protect the fruit from possums and birds is much easier and more cost effective.
Not all dwarfing rootstocks are equal!
Some dwarfing rootstocks will restrict fruit tree growth to 1.5 metres, while other dwarf fruit trees may get as tall as five metres. It’s going to be difficult to pick the fruit from the top of your “dwarf” fruit tree if it’s five metres tall!
It is important to know exactly which dwarfing rootstock you are getting, so that you know how big the fruit tree will get. Often this information is difficult to obtain from even your local nurseries. As a general rule, we advise against buying fruit trees from the large hardware chains. They’re usually on rootstocks that are less than ideal and will mean that you’ll become a slave to their rampant growth habits.
Instead, we encourage that you buy your fruit trees from other suppliers that will provide you with the details about the different rootstocks available. These suppliers will usually provide you with plenty of advice about which fruit trees and rootstocks are best for your situation. If you’re looking for grafted fruit trees to plant in Melbourne, some of the better suppliers are:
- Telopea Mountain Permaculture (Monbulk, Vic)
- Daleys Fruit Tree Nursery (Online, NSW)
- Yalca Fruit Trees (Online, Nathalia, Vic)
- Woodbridge Fruit Trees (Online, Tasmania)
- The Diggers Club (Online, and various locations in Victoria)
Citrus tree rootstocks
There are many rootstocks suitable to Melbourne’s soil and climate available for apples pears, stone fruit, and other fruit trees. However, the only rootstock that should be used for growing citrus in Melbourne (and all of Victoria) is “Trifoliata”. Any other citrus rootstocks (including the citrus trees sold by Aldi) will perform poorly and will most likely die. Don’t bother wasting your money! There is a dwarf trifoliata variety called “Flying Dragon” which restricts most citrus to only 1.5 metres tall and is ideal for growing citrus in pots. Trifoliata rootstocks are suitable for:
- Native finger limes
Want to know more?
Winter in Melbourne is the time to attend to our fruit trees. It is important to invest time and effort into fruit trees during winter, to ensure that we have successful fruit crops in summer. Take a look at our guide on caring for your fruit trees this winter.
If you would like further information on fruit trees, then please sign up to our Science of Edible Gardening Workshop Series. The May and June workshops (repeated annually) in the series focus heavily on orchard set up and management.