RHS Horticultural Advisor Lenka Cooke shares her expert advice on this useful skill
Easy guide
In grafting, two separate parts of plants are brought together and joined so that they function as one single plant. Natural grafts can occur where two tree branches grow so closely and tightly, typically in a hedge, that they fuse and the parent plants become a single one.
Artificial grafts usually involve a rootstock comprising the lower parts of a plant including the roots and a scion, which is the aerial portion of a plant – stem and leaves. A join is made using a very sharp knife or other implement so that the conductive tissues of the two parts are exactly matched. If held tightly together and not allowed to dry out by covering with wax or plastic tape, they fuse, becoming just as strong as an ungrafted plant. For grafting fruit trees winter whip grafts are usual; a sloping cut at the base of the scion is made, and a ‘tongue’ or sliver cut into the slope. An exactly opposite cut and tongue is made on the rootstock. The two are brought together so the tongues slide tight together and are securely bound with tape until they knit.
There are many other techniques too; bridge grafting is used to bridge areas where rabbits or deer have chewed away the bark. Most garden centre trees are produced by budding, a form of summer grafting. Budding is where the scion is a mere bud and another method is adding different shoots to mature trees by top or frame grafting.
Plants commonly grafted include apples, cherries, pears, roses, plums and many ornamental plants. There are limits to what can be successfully grafted; apples cannot be grafted onto pears or cherries, for instance. However, closely related genera can sometimes be grafted – pears are commonly grafted onto quince rootstocks, for example. Curiosities include the ‘pomato’ where a tomato is grafted onto a potato so that tomato fruits can be gathered and when the tomatoes are finished, th
