I have a Meiwa kumquat tree that was grafted to Kuharske Citrange. The combination is not compatible so I planted a Flying dragon seedling next to the Kuharske. I scraped the surfaces of the meiwa and Flying dragon to expose their cambium layer. I wrapped the 2 together with Teflon plumbers tape an put a clothespin on them to hold them together. 2 years later I have success.
Just a simple update on this tree. It has a total of 3 growth spurts and is now in a 5 gallon bucket well. When winter sets in I will place a light bucket over top to provide light and heat to keep it growing over the winter.