I bought my Harvey lemon from Haris Nuersery and just found out that the sour orange rootstock was a rooted cutting or an air laying when I tranfered the tree to a bigger pot.
Harvey lemon grown from seeds on its own rootsystem was already hard to survive over the winter in zone 8a. I was very disappointed when the sour orange rootstock is a rooted cutting. I then grafted a few branches of harvey lemon on my trifoliate seedlings to retain the gene just incase. The success rate was 100%, but I douted that the future scionwood overgrown issue might somehow occurs at the later years.
The winter season in Atlanta was not so bad in the last 30 years, so I hope that Harvey lemon on trifoliate rootstocks will make it through. I am on my own experiment on multiple grafts on a single rootstock and multiple rootstocks on a single scionwood just to see whether or not it'll boosts growth rate as well as mature rate and if success, it'll definitely help to speed up the hybridizing program. I will publicate the method when success.
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