I was overly hopeful using that word “consensus” I guess 
Do you know if Nurseries use D. Lotus as rootstock in America? I have read that to be an issue for early leafing out, and then damage/death.
I see that Spain uses D. Lotus to get a 1-2 week jump on harvests so some of those come to other European countries onto D. Lotus rootstock as a byproduct or people just use them out of ignorance? Just another thing we can add to the list of likely suspects.
The dreaded words…it depends.
Chinebuli has done perfectly fine for me in zone 6b. I think my microclimates 7a, but that’s nitpicking.
Yes, it is common in the western U.S. and somewhat in Japan. There are D.kaki cultivars that have not done well on it in southern CA, e.g. Matsumoto Wase.
Have you ever had a cold summer to see if it still ripens? I am understanding that D. virginiana will more successfully ripen it’s fruit even if it requires freezing weather to help, while I understand that D. Kaki can end up with a failure to ripen the fruits in short cool summers.
I have short summers sometimes at our latitude 51N is why this interests me.
Last year was my first crop, but they ripened plenty early for me.
Nitpicking – I wish. Z7A equates to an average low at 0 F; Z6B is -5 F. As I recall, it has been claimed that Chinebuli survives temperatures below -10 F. I’m actually inclined to believe 0 F to -5 F, so your testimony doesn’t surprise me. And I’m willing to believe -10 F with some evidence. But Cliff’s website says it survived “during one of the coldest winters we have ever experienced (the Polar express) with temps dipping into the mid-teens.” I assume that means mid-negative-teens. The difference between -15 F and 0 F is not a mere nit.
He still claims zone 6 on his website which goes down to -10 though. As others said I have many plants that are zone 6 and up that survived a -15 snap this year. Many nursery claim buried treasure huckleberry to be zone 6 but it survived my zone 5 weather just fine. Buried treasure huckleberry is evergreen so I can see it still made it. While not out of dormancy yet my Necta Zee Nectaplum seems to have survived the -15 degree temps as it still bends too. Pretty much every website claim the Necta Zee Necta plum hardy to zone 6 or -10. We have had a -15 degree this season and it has gotten into the negatives a lot as well. I think within the past week it was in the negatives but only like -2 but that is still more uncommon that past winter. Another note is where do you even get Chinebuli persimmon? It is not listed under any website for sale that I can see.
Another persimmon many claim is hardy to zone 6 at least is Ichi Ki Kei Jiro. Many claim it is the hardiest of kaki persimmon. I wonder if anyone in zone 5b borderline zone 6 like me has grown them. I may test one out.
I tried ‘Sheng’, ‘Great Wall’, ‘Ichi Ki Kei Jiro’, ‘Hokkaido’, ‘Rosseyanka’, ‘Nikita’s Gift’, etc. in zone 6a years ago. Most couldn’t survive their first winter. ‘Rosseyanka’ looked good for 3 years until the very late cold-snap of 2007 hit when sap was rising, it leafed out and died from the top/down to the ground. But that was an unusual cold-snap that also killed almost every dwarf Japanese red maple in town.
2021 winter cold blast of -20°f at night for a week killed most of my hybrid persimmon seedlings and advanced pawpaw seedlings. Yet 5 year old ‘Kasandra’, ‘Zima Khurma’ and ‘Mikkusa’ were unscathed.
I did read the same thing OP said where lotus comes out earlier. Were they grafted onto Lotus or American?
I’ve only had one lotus rootstock, was a box store closeout of a commercial type for $1. I knew it wouldn’t make it but I wanted the lotus. It still sprouts up 6’ tall each year, dies to ground level over winter.
I agree there are many variables, but any kaki in zone 6 is doubtful for long-term fruiting. The odds are too high of a late freeze, a super cold front, etc comes along and wipes them out. Kakis for me are reasonably reliable, I only lost some of the less hardy ones, but pomegranates are the equivalent of kakis for my zone. They can live for several years but the odds of making it ten years without dieback are pretty small. I think this might be the year I lose my nice 20’ tall poms, they are about five years since last dieback but we got some really cold waves this year.
Chinebuli could be more hardy but based on past reports of “super hardy” figs poms etc which didn’t pan out I am a skeptic. For Cliff he had hundreds of kakis and some will just be in lucky spots when you have that many. Hopefully I am wrong 
I had Ichi Ki Kei Jiro for a number of years. I live in a very mild zone 6, many years (this year included) I see temperatures firmly in zone 7. I had it survive 5-6 years and got fruit ripened off it twice. The fruit were far better than the Fuyu I see in the stores.
I also lost it in a pretty typical zone 6 winter. This was about 4 years ago
I would say if you have a pretty dry zone 6 winter or one in which there is good deep snowfall you might have a chance.
I’ll be grafting the rootstock this spring. I will be grafting a hybrid to it this spring.
Scott
I’ll be trialing this one in Z6 Persimmon Zirochka/Zirocka/Zirotschka
I’m hopeful it does well but will be making backup grafts next winter just in case.
You’re scaring me. I’m on borderline Z6/Z7. I’ve had IKKJ since 2015. It survived ~-3 F a few times, -5 F once or twice, and -7 F once as I recall. All of this was mid-winter, never spring. This year were had -7 F briefly one night. I’m hoping that the trees are tough enough in February. Fingers crossed.
But your data is useful, if depressing. “Pretty typical Zone 6” seems to be the boundary,
Hi Randy, do you have a guess-timate of that temperature that maimed those three D. kaki’s ?
Any idea what the lowest of those were, and what low temperature killed it?
Sorry, too long ago, 1998?, but it was very average for Topeka KS. They were small, I put loose white plastic spiral sleeves on each to prevent sunscald. Cliff recommended this selection to try as he had been stationed at Ft. Riley (60 miles west), in the 80’s, was somewhat familiar with the climate. If I were to try those again I would want to plant them in early March instead of fall. Our difficulty here is average winter temp. fluctuation from 0° to 60’s all thru winter with almost constant wind and lots of sun. Then a late cold snap, guaranteed.
I think hybrids have more potential.
I got the IKKJ yesterday. I am starting it in March. The worrying part is it came from Florida. The hybrids do not have the fact that they are non astringent. If you have an astringent they work though. To me that would be the big difference of an asian vs an American.
Good luck. I thought I was zone-pushing planting IKKJ here on the border of 6B/7A.
You’d best keep it in a very large pot for a couple years before planting it. Even then, it’s a huge stretch.
That is the plan with all my plants.