A fruit tree rootstock is the stump of a related species which already has an established, healthy root system, and to which a separate fruit tree is joined by grafting or budding. The resulting fruit tree will be stronger, quicker to establish and will take on the desirable features of the rootstock itself. The join between the fruit rootstock and the main fruit tree (also called the scion) is easy to identify. It will appear as a bulge or kink just a few inches from the bottom of the stem where the wood has knitted together.
If allowed to grow naturally, most fruit trees will easily reach heights of at least 4.5m (15ft). Such tall fruit trees would be difficult to harvest as well as being far too large for most people’s gardens. To overcome this problem, most fruit trees are grafted onto the roots of a related species that has a more compact habit, or some other particularly desirable characteristic such as vigour or disease resistance.
So we can limit the height of a fruit tree by grafting it onto dwarf rootstock which will allow it to be grown in a smaller space than if it were grown on its own roots. Such dwarf fruit tree rootstocks will reduce the ultimate size of the tree to such an extent that they can even be grown in large (60cm/2ft diameter) containers on your patio. However, it is worth noting that the container itself will also restrict the growth of a patio fruit tree. Therefore most miniature fruit trees will reach an approximate height of just 1m, but will grow into taller trees if they are not grown in containers.
One great advantage of dwarf rootstocks is that they have no influence upon the size of fruit itself, so a dwarf patio fruit tree will produce the same sized fruits as a large orchard sized tree.
When buying fruit trees online you will often see a rootstock described by a name or code such as M27. This can be particularly important when deciding what sized tree is most suitable for the space available. Take a look at our table of fruit trees to check that you have the right fruit rootstock for your garden.
|Fruit Rootstock||Rootstock name||Rootstock type||Ultimate Height|
|Apple||M27 (Similar to: P9)||Extreme dwarf||1.2m (48")|
|M9 (Similar to: Pajam 2, Pajam 9, P2)||Dwarfing||1.8-2.4m (6-8ft)|
|M6||Semi Dwarfing||3m (10ft)|
|MM106||Semi Dwarfing||3-4m (10-13ft)|
|Cherry||Gisella 5||Semi Dwarfing||2.4-3m (8-10ft)|
|Gisella 6||Semi Vigorous||3-4m (10-13ft)|
|Colt||Semi Vigorous||5m (16ft)|
|Peach, Plum, Apricot and Nectarine|