You say they are both seedlings? Hmmm. Well, no experience with either, but I have a Clem-Yuz seedling that is roughly 8 years old, and it looks like it will be giving me a good bloom this year. It had a handful of blooms last spring, but nothing came of it. This year at least half of the top-most portion looks to have buds developing. The plant is about 7 to 8 feet tall.

I started cuttings and a one graft (onto trifoliate) from the top-most growth last summer. When those become more vigorous, I'll probably get rid of the mother plant, because it's just too big.

[https://www.houzz.com/discussions/thomasville-citrangequat-zone-6b-success-dsvw-vd~1818226?n=84[(https://www.houzz.com/discussions/thomasville-citrangequat-zone-6b-success-dsvw-vd~1818226?n=84)

6b success

Steve

Sounds like I have a ways to go unfortunately, it sucks that even if you can get a hold of these cold hardy things you can't get a grafted one, looks like my Keraji grafted to Rubidoux will be grown up and in ground first

Citrangequat should be okay growing on its own roots, because of the kumquat ancestry.

Yes, it would reach fruiting age sooner on rootstock, but citrangequat is fairly fast growing and will likely reach fruiting stage at around 3 or 4 feet high, which in your climate with protection over the winter could be about 3 years, maybe slightly more.

Keraji can only survive down to about 8a unprotected and is not quite as hardy as citrangequat. (still a good idea to protect citrangequat where you live)

My Citrangequat is 4 feet tall now, its a trifoliate hybrid rootstsock itself so that isn't the issue, I worry I need up to 2 more years and several feet before its bearing size and not so easy to protect........the Keraji is a mandarin with a bearing scion already and is on trifoliate so I assume it will stay smaller and be easy to protect.