Growing an apple tree from seed may create an apple tree that’s different than its parent. All commercially offered apple trees are grafted trees. A branch, referred to as a scion, or even a grass from a desired apple tree is grafted to a acceptable foundation or rootstock. Deciding on the best rootstock is critical as it helps to ascertain the size of this tree, disease and pest resistance and what circumstances, such as drought or flooding, the tree can withstand. Rootstocks are generally categorized by their ability to ascertain tree size.
Rootstocks for Really Small Trees
In the 1990s, the East Malling Research Station in Britain started to classify apple rootstocks with their magnitude. The M27 (Malling 27) rootstock has one of the greatest dwarfing results on apple trees, making them grow no longer than 6 feet tall. M27 allows fruiting at two years and results in the tree to be immune to this fungus Phytophthora, which causes crown rot. However, the tree is susceptible to mildew and fireblight. The Polish P22 (Podkladki 22) rootstock also produces a tiny tree, but the tree is less susceptible to mildew and fireblight. The G65 (Geneva 65) rootstock was created particularly for North American conditions. G65-based trees are resistant to crown rot and fireblight and are just marginally larger than M27.
Rootstocks for Little Trees
M9 was the very first rootstock to become broadly available and it is still used today. M9-based trees reach 8 feet and fruit in two to three years. The major drawback is that the susceptibility to fireblight and lack of cold hardiness. The G11 rootstock is similar to M9, except the apple trees are very resistant to fireblight and may not fruit until three to four years after planting. Bud 9 (Budagovsky 9) is just a rootstock similar to M9, but it has very good winter hardiness.
Rootstock for Medium Trees
The M26 rootstock produces a medium-sized or semi-dwarf tree of about 10 feet. It results in the apple tree to fruit following three to four years. M26 has similar properties to the dwarfing M9 rootstock and trees are susceptible to fireblight, crown rot and the woolly aphid. In contrast, the M7 rootstock produces a medium-sized tree resistant to fireblight. The G30 rootstock is well adapted to North American states and rises a productive apple tree. G30-based trees are resistant to fireblight and can withstand flood. The most important disadvantage of G30 is that trees need permanent staking.
Rootstocks for Big Trees
Several rootstocks create large, vigorous apple trees 14 to 18 feet high, but these trees take up more space and are more difficult to prune. MM106 (Malling-Merton 106) permits fruiting in three to four years The MM106-based trees are resistant to woolly aphids, however not fireblight or crown rot. The MM111 rootstock grows well in poor soil and apple trees begin fruiting in four to five years. MM111 benefits are good general disease resistance and the ability to grow well during drought conditions. The Bud 118 rootstock is similar to MM111, but has much better cold hardiness and trees symbolize large traditional apple trees.
Interstem Rootstocks
An interstem rootstock consists of 2 rootstocks, one rootstock grafted on top of another. The scion, which establishes the apple variety, is grafted to the top rootstock. By choosing the right blend of rootstocks, you can design an apple tree suited to your specific area and conditions. As an instance, a M9/MM111 rootstock has the good qualities of M9, however far better drought tolerance and a stronger root system. The most common combinations utilize MM111 or Bud 118 on the underside with different rootstocks grafted on top.