I live in zone 7b(very close to 8a) and I am looking to add a satsuma to my yard. I will place it in a very protected/sunny spot along the southside of my house. I plan on winter protection. I realize, though, that I need to most cold tolerant plant possible. So here is my question, I am looking to buy grafted plant. For the plant part, what you recommend, Owari or Brown's select? For the root, Trifoliate or Flying Dragon?? What combo of those would make the most cold hardy plant? Thanks for your input.

Armstrong Early  extremely early
 Brown's Select  very early
 Port Neches  very early
 Owari  early
 Kimbrough  early

I have my largest satsuma situated up against my house on a south facing wall. It is a Kimbrough that was supposed to be grafted on regular trifoliate but I suspect that it really is on Swingle after studying the leaf pattern on a few shoots that shot up from the rootstock. I was a little worried about it being a little less hardy for this reason but it has been doing very well after nearly 5 years in the ground with minimal protection.
I have since grafted Nuclem and Early St Anne to those rootstock sprouts and both grafts are doing well too. I had a chat with Sherwood Akin a few years ago and he informed me that through his experience he was convinced that St Anne was one of the most hardy satsumas out there. Of course now we have some of the numbered China selections available that I have yet to test.
Out in the middle of the yard I have some other recent satsuma high grafts (Brown's Select and a couple of others I can't recall at the moment) that have been totally unprotected this winter that are also doing fine. My yard thermometer has recorded a low of about 15 degrees this winter.
As an experiment I grafted a seedless Kishu -one of my absolute favorites, out in the yard and suprisingly it is doing just as well as my satsumas and even slightly better than some my other hardy citrus. This one looks like a keeper if I can manage to get some ripe fruit before freezing weather sets in for us each winter.

Armstrong Early, Early St Anne and Louisiana are early satsumas. Brown Select, Kimbrough ,Owari and Port Neches (BC-!) are late satsumas. The first year that Armstrong Early bears it is terrible but gets better as the tree gets older. Oba Wase is one that ripens between the early ones and the late ones. Miyagawa and Okitsu are also early ripening satsumas. Miho and Seto are ones that the seed were obtained from Japan by Dr. Jerry Parsons and Larry Stein with the
Texas A&M Extension service several years ago. I have never seen a bad satsuma including the seedling satsumas. Wase means early

bump any updates?

As far a variety is concerned, any of the above suffestions are fine. Eyeckr has had good luck using high grafts. so I would suggest FD as a rootstock with the scion grafted high. That would make the resulting tree easier to protect in case of freeze and provide the extra hardiness offered by trifoliate.

I might add that I have had good success rooting Kishu and I suspect it would do ok on it's own roots.

Makes it harder to protect from freezes by banking with dirt. The higher the graft, the more dirt must be banked.