I hear you on the zone pushing thing. I too desperately want Asian persimmons, jujubes, etc.

I think that the problem with the approach you suggest is that the solar gain in such a small structure isn't adequate on those one or two really cold nights that would prove fatal to the plant.

On the palms and cycads board, a poster named Artictropic (or perhaps its Artictropical) has these amazing photos of very large palms he grows outdoors all year round in Zone 4 northern Utah at something like 5000 feet up in the mountains. He uses thick foamboard boxes and a few cfc lights to keep the plants alive all winter. I think the same approach would work very well for persimmons.

thanks for the insight denninmi, i may give that a shot. as for jujubes, go ahead and plant them, i have had 2 living for 5 years on a small mound in the center of the drive with no winter protection at all. they both fruited the first couple years, then one died at the graft so i let it sprout from the root to use as a plinator, they are VERY late to leaf out, and they do put on lots of new growth too late in the fall to harden off, but they do get a little bigger each year. i cant help but think if i put some effort forth, they would do much better, but since i want them small i just let whatever happens happen.

I think it's worth a try. I had a small greenhouse thing made of construction plastic and pvc pipe, by no means airtight, and there was still a noticeable temperature difference. The wind destroyed the plastic, though, so you might try something glass if it's windy where you are. If you're handy, I've heard of people getting old windows for free or cheap on craiglist and attaching them together into a box shape. If you have a terribly freezing night, maybe you could put buckets of boiling water in there, or something.

Without protection the persimmon won't make. As far as the jujube goes with the right cultivar you may be OK. I would try and find the earliest ripening selections available. Do a google search for Roger Meyer and Jujubes. He has lots of jujube selection and can advise you on which ones might do the best for you.

As far as persimmons go have you tried Rosseyanka? It is a American x kaki and is reported to taste like a Kaki. It is also hardy into zone 5. There are also several american persimmon seleections with large fruit such as Prok and Yates.

David

please tell me something about my persimmon.
it is about 24 inches tall, it is from seed and I am not sure if it came from Fuyu or Hachiya persimmon fruit.
somehow it survived ontario winter although it was very younge and small and not protected. This winter I plan to put some winter protectio, just a bit. I would like to know if it ever grows big will it produce any fruit without another persimmon and will fruit be edible.

Please, write me as much as you can,
Thank you all