A English double split graft it is the least simple to do among the scion grafts (different from buds and grafts for approximation) but it is also the one with the best success rates on young plants and also on the vine. If practiced to perfection of course.
The advantage of a English double split graft compared to the other split graft it is in the vast promontory area of contact between the rootstock and the scion.
However, the subject and the scion need to have the same diameter, and a very sharp splitting knife is needed because the cut must be precise and the grafting surface where the welding will take place must be perfectly smooth.
The best time for a English double split graft it runs from the beginning of March to the end of April, when the seedlings are more elastic and consequently the risk of breaking is reduced. The operation is, as we said, rather delicate. Let's see it.
English double cleft graft: procedure
- The subject is cut at an angle with the lower part inwards, making the surface of the cut as smooth as possible.
- Still on the subject, a second deep incision is made (slightly inclined and half the length of the previous cut) in order to open the rootstock in two tabs.
- We move on to the scion and prepare it in the same way as the subject: first with the perfectly smooth oblique cut, then with an incision that must have the same inclination as the cut made on the subject.
- After having prepared them, the subject and the scion are grafted by 'fitting' the respective tabs.
- Finally, the parts are tied taking care not to choke the branch and the exposed surfaces are isolated with mastic.
To avoid the risk of throttling, which in the case of English double split graft it is particularly high, it is advisable to replace the binding every week until welding has taken place.
Alternatively, elastic ties can be used, which adapt to the enlargement of the shaft and in this case can be left until successful grafting.