A good crop of runner beans thanks to a 5 year old bed of biochar. (sorry, I just had to put that in.) So much so that I got fed up with eating them, freezing them and picking them. I tell my neighbour to help herself, but she is a bit loathed to do so. So I just let them grow, thinking to shell them later to use the beans some other way. I grew White Lady from saved seed, and a few weeks ago saved some more. No black ones. During the shelling I found one that contained jet black beans. In all my years of gardening I have never come across a black bean before, and I don't ever recall my father doing so.. (Taking account of the fact that the beans are eaten green).. By the time I had finished shelling (between jobs) I had found a total of eighty. Two of the pods were still joined on the flower stalk, which makes me think that it was a single plant that produced them. Comments please, and I am sure that it wasn't the black leaking out of the biochar.