Rootstocks for Cherry Trees

Cherry trees present a particular challenge because when grown on their own roots they are potentially the largest of all fruit trees, certainly much larger than wild apple trees. Until relatively recently there was not much that gardeners or commercial growers could do when growing cherries but accept that the trees would be large, would take up a lot of space, and most of the cherries would be so high up that the birds would get there first. Fortunately recent research programmes have resulted in new rootstocks that produce smaller more manageable trees - useful for commercial growers and ideal for gardeners.

There are a couple of factors with cherry rootstocks that are not usually found in rootstocks of other species such as apples. Firstly, the size class of cherry rootstocks can be surprisingly variable - the scion variety and climate have a bigger effect than they do with apples. Secondly nearly all sweet cherry varieties belong to the species Prunus avium, which is naturally a relatively large (20ft+) tree, whilst most cherry rootstocks are of different (i.e. less vigorous) Prunus species, and this can sometimes cause incompatibility issues.

Gisela 5 (G5) semi-dwarf rootstock

Gisela 5 is rapidly becoming the rootstock of choice for gardeners who want a cherry tree with manageable proportions. It produces a tree about 10ft tall after 5 years or so (roughly equivalent to the apple M26 rootstock).

Cherry trees on Gisela 5 are not always self-supporting so you will probably need a 6ft permanent stake or other means of support. Training against a wall or trellis works well with Gisela 5 (and also means you can more easily cover the tree in early summer to keep the birds away). It is important to provide good growing conditions, including regular feeding and watering, and to keep the area around the tree free from competing weeds or grass. However these are minor inconveniences compared to the attraction of being able to pick your own fresh cherries, and if you can provide the necessary growing conditions then cherry trees on Gisela 5 are reliable croppers.

This rootstock was developed in Germany and is a cross of Prunus cerasus and Prunus canescens, both naturally small forms of flowering cherry.

Krymsk 6 semi-dwarf rootstock

This is a Russian rootstock developed from Prunus cerasus, roughly similar or a bit more vigorous than Gisela 5. This rootstock has a very wide climate range, being tolerant of hot climates and also very cold-hardy.

Gisela 6 (G6) semi-vigorous rootstock

Gisela 6 produces a slightly larger tree than Gisela 5, roughly equivalent to the apple MM106 rootstock. The main advantage over Gisela 5 is that it is much less fussy about soil conditions, and it comes into bearing at an earlier age.

Krymsk 5 semi-vigorous rootstock

A Russian rootstock, developed from Prunus fruticosa and Prunus lannesiana. It is similar to Gisela 6, but has a wider climate range (both colder and hotter climates).

Gisela 12 (G12) semi-vigorous rootstock

Gisela 12 is best considered as a semi-vigorous rootstock, but the extent of dwarfing effect is considerable. In most situations it produces a tree that is usually slightly more vigorous than Gisela 6, although with some varieties it may be more dwarfing and with others it can approach standard vigour.

Apart from its uncertain size, Gisela 12 is a highly productive and precocious rootstock, self-supporting, compatible with all cherryvarieties and tolerant of most soils.

Colt semi-vigorous rootstock

This rootstock is a form of the seedling cherry Prunus avium, crossed with the less vigorous Prunus pseudocerasus.

It is a good rootstock for growing cherry trees in large gardens and community orchards. It produces a tree with a height of 12ft-14ft in European conditions and somewhat larger in North American conditions. It tolerates poorer soils than Gisela 5 and needs less looking after. It's also useful for large cherry fans. Colt is roughly comparable to the apple MM111 rootstock.

Colt has good compatibility with nearly all cherry varieties, possibly excluding Van, and some resistance to bacterial canker.

It's main drawback in US conditions is that it is not particularly cold-hardy.

Mahaleb vigorous rootstock

A traditional seedling cherry rootstock which produces a large standard cherry tree, with a mature height of 16ft - 20ft. It is perfect for traditional orchards, although it is quite slow-growing and the large trees might be difficult to harvest from - unless your objective is feeding the local birds.

Mahaleb is suitable for a wide range of soil conditions. If you have drought conditions this is the best cherry rootstock. Conversely, if you have heavy wet soils it is one of the worst.

It also has the advantage of producing a slightly smaller tree than the Mazzard rootstock (see below) and is generally more disease resistant and has slightly better cold-hardiness.

Mahaleb is not fully compatible with all cherry varieties.

Mazzard F12.1 vigorous rootstock

This is the original traditional Prunus avium cherry seedling rootstock and produces a very large standard cherry tree, with a mature height of 20ft or more. It has been in use for centuries (if not millenia) and is compatible with all current cherry varieties. It is reasonably cold-hardy, though not as hardy as the Gisela series.

The F12.1 clone is a standardised form of Prunus avium which gives a consistent full-sized tree (i.e. it is propagated rather than grown from seed). It has some natural resistance to bacterial canker, which is one of the most widespread diseases of cherry orchards.

Introduction to rootstocks