I would wait until the bark was slipping again & T-bud about 12 inches up from the soil.

The reason for this is it would produce a very nice tree rather quickly with a nice fat rootstock like that.

As most of you know I don't like cocktail citrus trees.

When should I expect the bark to "slip"? Do I do the test described above weekly, monthly, sorry for all the questions, I'm a complete newbe to this.

I am not looking for a tree with different fruit, just oranges.

When the plant is in active growth.

Thanks, everyone for the help / advise. I will put it on hold until March, I'll be back then for further help if I get stuck.

Good luck !

Update:
I contacted John Bash at the UCR Citrus Clonal Protection Program in Decmber. I told him my situation and he offered me a few buds. I told him what variety but they didn't get cut in the January cutting, now I have to wait for the June cutting.

Is that going to be ok to graft in June?

The rootstock has been dormant until the last week, it is now starting some growth at the base I don't know if it is the original citrus I trimmed or rootstock.

It is completely okay to bud/graft anything as long as the bark is slipping meaning that the rootstock, which is to be grafted, is in an active phase of growth.

Igor

I am having a hard time corresponding with John Bash to get some buds and am thinking that it may not happen but have seen growth and am hopeful.
The growth at the top and some of the bottom is root stock. At the bottom where the original graft was made is growth that is citrus.
I am thinking I should cut the rootstock back to give more energy to the citrus, is that correct, if so where do I cut?
Are there any other suggestions?

The whole tree



The base / graft

You are right. It seems this is the original tree.
I have never seen such a low graft. The tree must have been buried too deep.
Now you are in the same condition than the other tree. You can cut every part of the rootstock, but grafting the rootstock trunk is still an option.
It's up to you.

If I want to keep some rootstock in case I get some buds to graft can I remove all growth from the rootstock and leave the trunk. This way all the energy goes to the citrus?

Yes, you can do that but it is a short time solution.

I'm confused as to what you are asking... The entire plant you have pictured is rootstock.

Its very hard to distinguish but all the growth coming out of the little stump on the left is monofoliate which is Gardennewbe's 'citrus'. You have look very carefully to sort it out. The larger trunk of the tree on the right is trifoliate that has new growth intermingling with the monofoliate leaves making the whole thing appear to be rootstock.

If you want that very low grafted (or planted deeply) 'citrus' scion to thrive I'd lop that trifoliate all the way out of there down to the soil level. Alternatively you could keep the trifoliate on there to graft another variety onto later but I would make sure to rub every single sprout that comes out of it until you do. This will keep all current growth to the 'citrus'. I grow many multi grafted trees. Looking at the vigorous, husky growth of this rootstock though I think anything grafted onto it will probably outgrow the lower grafted plant. It would take some work to keep two varieties in balance in this particular case.

Whoever planted the tree in the container has planted the tree to deeply, and has buried the graft. It looks like the tree has been growing in that container for some time. If however, it has just been recently potted, I would raise the tree to its proper level. Personally, I would get rid of all of the Trifoliate growth and grow the tree as a citrus tree, but then I have never been a fan of multiple varieties growing on a single tree. - Millet