The apple tree is a rather easy plant to graft, using one of the most widely used techniques, the diametral split graft. This type of operation is performed by grafting plants with similar morphology, in order to have a more vigorous and resistant specimen.
The apple plants are deciduous trees that, depending on the variety, can reach heights of 10 meters. The choice of graft holder allows to obtain plants suitable for different areas and climatic conditions, as well as for soils with different composition. The best time to practice this technique is that of the months of February and March, while the apple trees should be planted in the autumn season, when there is still no risk of frost.
Apple tree grafts
The most common apple rootstocks are: the franc, the paradise and the dolcino.
The FRANCO is certainly the one that has the greatest diffusion, not only in Italy, precisely because of the dominant feature of robustness. It goes into production rather late, that is, after the fourth or fifth year. The PARADISE is quite delicate and originates a root system that is often inconsistent; It is also not advisable to use it in areas that are poor in water. SWEET has very often negative characteristics. It does not develop much roots, originating medium-sized plants, but which fructify more quickly than the franc, even though their duration of productivity is shorter.
These last two rootstocks have been used with great success for clonal selection.
The result obtained by the English researchers of the East Malling center was a cataloging that we report below, citing the most important clones. The abbreviation M derives from the name of the East Malling experimental center.
M II: it is a rootstock quite vigorous that reaches a remarkable productivity;
M IV: it is defined as weak, because it develops little vigorously. This also rootstock must be helped in growth;
M VII: medium vigorous, it is a rustic rootstock that adapts well to both dry and wet soils: It has good anchorage even in the lightest soils. It is sensitive to radical tumors (Agrobacterium tumefaciens).
M IX: is a rootstock that gives rise to dwarfed plants. It must be buried in a warm environment and needs very fertile soil. It develops roots that sink little and therefore, in many cases, should be helped with support.
M XI: it is very vigorous and rustic, it adapts well to all soils, in loose soil it produces early.
MXII: this rootstock is able to originate plants of good vigor, and manages to be similar with a fair number of varieties;
MXIII: also considered vigorous, this subject lends itself very well to rooting also in clay soils;
M XVI: is another subject considered very vigorous. The only disadvantage, if we can say so, is that with respect to dwarfing subjects it delays the entry into fruiting;
M XXVI: it is the weakest rootstock among the recommended ones: It has an early fruiting but needs tutoring. It prefers fertile and deep soils with good drainage.
Other clonal rootstocks are those selected by the Malling Merton laboratories (M.M.). The rootstocks marked with the initials MM are resistant to the wool aphid.
M.M. 104: considered very vigorous and of considerable fruit production;
M.M. 106: it is medium vigorous. It has high yields with an early harvest. Fears drought in too dry and permeable soils. In loose land requires tutoring;
M.M. 111: it is vigorous, resists drought well but fears radical asphyxia in heavy soils. It is suitable for deep and loose soils.
Apple tree graft holder: Apple tree graft
As said the best technique to graft these plants is the split one, also called a marza, as it intervenes in a branch of the mother plant to graft a branch of the chosen plant, called marza and endowed with buds; in the case of the apple tree, the buds must be a maximum of three. The scion is chosen among the more robust branches, but it must be chosen with a rather small diameter, since it must be inserted. The part to be grafted must be cut obliquely, to facilitate insertion into the chosen branch. The apple tree graft holder must be chosen from the side branches, taking care to choose one with dimensions not exceeding 2 centimeters. This should be cut at a distance of about ten centimeters from the trunk, in a clear and linear way. At the center of the surface obtained, a slit must be made, in which we will proceed with the insertion of the scion. It then proceeds to carefully tie through the use of raffia or special materials, remembering to cover the cuts with mastic to avoid the onset of rot. The graft should be covered with plastic, checking that there is no accumulation of moisture. If the process is successful, the gems can appear within a month.