hi

my fall back would be to plant a deciduous tree.. when it is dormant.. w/o leaves ... to avoid transplant shock

but.. some suggest fall planting.. and other spring planting for oak ...

and i surely dont know when is better in japan ...

but since it is very hard to winter over dormant trees indoors.. i think i would get it done.. right after leaf fall ... as i would figure i have a greater chance killing it indoors or in that small pot in winter.. as compared to letting mother nature take care of it ...

and all this presumes.. it is fully zone appropriate for your climate... of which i don not know....

ken

Basically with Ken,
Assuming it is proper for your zone, then I would plant in fall, especially since the entire rootball will be going into the ground. From what I understand, bare root oaks in fall can be a problem due to not being able to store adequate water, but that would not be what you are doing. Overall, I try to plant most of our stuff in fall, it just gives it more time to develop roots before dry summer weather.

Are these Oaks native to the area you want to plant it? If so, then barring unusual weather, I think it would survive just fine assuming reasonable soil.

Arktrees

Is it just a camera effect, or is there quite a bit of blue on those leaves?

That thing is gorgeous

Take it out of pot and look at roots. If they are starting to circle, for optimum growth the tree shouid be repotted to a larger pot. In general potted trees can be planted almost any time of year if you can provide ample water to them and ground is not frozen. That said, I would follow the recommendations above and wait till fall.

Hi, everyone. Thank you kindly for your advice. I think I will do it in the fall. The oak is from Oirase forest in Aomori, Japan, which is in the northernmost part of Honshu island (i.e., the main island) of Japan and famous for its forests. I took the acorn in October and kept it in my refrigerator until March. It's been growing in my Tokyo office since then. I hope to put this tree in a field about 85 km outside of the city--a spot I know where it will be left alone. Based on the information I've found, it's natural habitat would be zone 6a and it will be going to zone 8b, which may or may not present a problem. In any event, I can't just leave it in a pot forever, so I'll hope for the best when I put it in the ground. In the meantime, I will check the roots and pot up if necessary. Thanks again!

When you do examine the root system, be sure to address any circling/pot-bound roots BEFORE/DURING the potting up process.