I've grown Dioscorea for many years, but I've only had it produce aerial tubers a couple of times in more than a decade. My Dioscorea is in a warm very dry spot on the south side inside the drip line of a large fir tree next to a big fig tree. It flowers more often then it develops aerial tubers, but the vine doesn't even come up every year. This year I didn't see any growth on it, but this summer was rather cool. It often comes up big on years after it was a no show, and it seems to do better in years with warmer springs. The spot it's in is really dry most of the year, so I know I'm not getting optimal growth out of it. I plan to move some of it, but I haven't decided on a new location. I sort of planted it as an optimistic curiosity shortly after moving in, then mostly left it to it's own devices.
I haven't spent a lot of effort with the plant over the years, but a couple of times I've gotten huge numbers of aerial tubers. Some folks miss the blooms because they are so tiny. The flowers are tiny pale balls about the size of a seed bead, but they smell amazing. The aerial tubers look like itty bitty potatoes, ranging in size from a dried pea to a large hazelnut.
A former neighbor of mine did a lot of work on perennial vegetables when he lived in my neighborhood, and he ate the ariel tubers, leaving the big tubers in the ground. He has a blog from his days in the PNW and he mentions Cinnamon Vine, but doesn't go into great detail about it. If you search his blog you'll find a bit more info. http://farmerscrub.blogspot.in
My Dioscorea is planted in the ground, so I don't know if being in a planter helps or hinders the vine. My vine, on good years, will turn into a massive sprawling vine that tries to take over the fig tree, so they can get quite big in optimal conditions.
I'm in Zone 8, but my yard is a bit of a cold patch on a north facing slope above the Columbia River, with gorge exposure.