Basically grow and use Oca much as you would potatoes. Store the tubers until spring in a paper (not plastic) bag or envelope in a cool but frost-free place. Note that a garden shed is NOT ideal for any sort of seed storage as they tend to heat up on sunny days.
In spring, plant about 1 foot apart. If planted too early, frosts will kill the tips; they may resprout but yields will be reduced a bit.
While waiting to plant, check your stored tubers every now and then from January onwards! They may well start to sprout before you are ready to plant them out . . in this case you need to put them somewhere (still cool & frost-free) like a tray to catch a little light, just like chitting potatoes.
If they dont get any light they will make a huge tangle of very long sprouts, which will snap when you try to untangle them. (snapped sprouts can be rooted in a glass of water though, and the tubers will sprout again).
Exposure to a little light stops the sprouts growing and makes them stay short & easy to plant. It’s just like potatoes. The plants are reasonably easy to grow and require little care other than weeding. Earthing up (as with potatoes) is thought to increase yields.
Now the crucial thing is that tubers only start to grow when days start to shorten, in November. It is vital to leave the plants a good week or more after they are completely killed killed by frost. We have found that even after the leaves have died down, food is pulled back into the growing tubers as the stems die down.
Our tubers doubled in size a fortnight _after_ the plants had been killed by frost. So do not dig too early! You may want to protect with fleece if an early frost threatens.
Due to Brexit some things grown for us in other countries will be in short supply or unavailable for the forseeable future. Thank-you for your understanding.