This has to be the weirdest thing but when I was putting away my planters this fall, I had to remove some of the annuals from the pots so I could store them. In one of the big pots that I planted myself in the spring, I saw something just below the surface of the soil that looked like a slightly red light bulb. I removed some of the soil and what I found astonished me! A giant sweet potato (see below with my fingers on the bottom right of the picture as a reference point). I did not plant the sweet potato nor do I recall seeing it growing in the soil but it must have, because there it was. At first I thought it was some kind of joke that Robin was playing on me but he wasn't home when I was emptying the pots. I then went to another pot and there was a second one - just about the same size.
As if that wasn't startling enough, I dug further down into the pot and found two very large yams. I could not fathom what had happened to cause them to grow in the planters but later I surmised that I do buy and use sweet potatoes and yams and we compost just about anything that is compostable so maybe there were some eyes from some of the compostable materials that grew into those veggies. Whatever they were, I was quite thrilled. I later went into the garden and dug up my 10 pounds or so of potatoes that we really did plant.
All in all, with 60 pounds of tomatoes, my sweet potatoes, yams and potatoes, it was a good harvest after all. And yes, how could I forget my several dozen zucchini? I've shredded a lot of that and put in my freezer for winter baking and soups.