Rootstock size-class matrix

By grafting a fruiting variety (the scion) on to a compatible rootstock, it is possible to reduce the mature size of the resulting tree. The extent of the size control is typically given as a percentage of the full-size or 'standard' tree.

The definition of a standard tree is not precise but is essentially a tree grown on its own roots without any rootstock influence. In practice a standard apple / cherry / pear / plum tree is likely to reach a height and spread of 5m-6m when planted in good conditions (apples perhaps a bit less, plums, pears, and cherries perhaps a bit more).

A dwarf apple tree is therefore likely to have an overall size of about a quarter of the standard tree, in terms of its overall canopy volume. The way in which the tree is trained will also have a considerable influence (for example most dwarf apple trees in commercial orchards will be trained to a height of 3m, which is well over 50% of a standard apple tree … but with very little side growth).

The following matrix shows the rootstocks used for each species by size class.

Dwarf
25%
Semi-dwarf
40% - 50%%
Semi-vigorous
60% - 80%
Full size
90% - 100%
Almond Krymsk 86
St. Julien
Apple M27 (15%)
M9
M26
Interstems
M116
MM106
MM111
Own-root
M25
Malus seedling
Apricot Krymsk 86
Torinel
Cherry Gisela 5 Gisela 6
Krymsk 5
Colt
F12/1
Prunus avium
Damson VVA-1
Pixy
St. Julien Brompton
Medlar Quince A Crataegus
Mirabelle VVA-1
Pixy
St. Julien
Jaspi
Pear Quince C
Quince Eline
Quince A
BA29
Pyrodwarf
Pyrus communis
Pyrus Kirchensaller
Peach / Nectarine Krymsk 86
St. Julien
Plum VVA-1
Pixy
Wavit
St. Julien
Torinel
Jaspi
Krymsk 86
Quince Quince C Quince A
Walnut Juglans nigra

Introduction to fruit tree rootstocks