The housemate forgot a sweet potato and it became wizened and studded with hopeful little fronds, so I glopped some of the finished compost from the large bucket at the top of the driveway into the big square planter that I have on bricks near the kitchen window, which had been standing fallow. The compost came with its own retained water, but I'll add some every day for a while and see whether it manages to produce any plants. According to Wikipedia the flowers are morning-glory-like and the foliage is edible.
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