Yep, go ahead and plant; it'll be better off in the ground than in a pot. Make sure to give it a good mulch, though...wood chips would be best. Be sure to water it well when planting, to eliminate air pockets around the roots, typical autumn/winter rains will take care of its water needs until shooting time in spring. If the leaves curl inward, it needs water, but as mentioned, shouldn't be an issue in an open location until spring/summer.
i couldnt figure out which way round the bamboo was to go in, so i put it were most of the canes show through the front for the colour, prob doesnt matter hey which way round its planted??????????
Bambooman here, I believe this is one of the best times to divide and plant bamboo. Because by now it is dormant and planting now will give it time to establish before shooting season. Which will again stress the plant less and you should get new culms early next spring. Good luck with your new bad habit. I hope you don't become too addicted I'm 19 species into mine and yes I can admit that I have a problem but I don't know of any bamboo anonymus. I wonder if there is a twelve step program for people like me? My biggest problem is I'm running out of room to plant my next 19 species.