Well, what else could you possibly plant? You can start a garden and reduce not only your spending at the grocery store, but also your risk of buying a fruit or vegetable that has been thoroughly...
actually you dig the hole twice as wide as the plant. here in Florida we add soil amendments. hence our saying; put a five dollar plant in a fifty dollar hole. also make sure the top of the rootball...
basiclly what you want is for the cambium layer in both plants to touch and make sure the cuts dont dry up, there are many many methuds. google "grafting" and find out