Posted: 16/11/2015 at 09:09
Sorry for not getting back to you sooner. My runner beans are still producing black seeds, but have stopped producing uniform purple pods. The developing pods start off green and then they lay down the purple as the pod gets bigger. However, green areas remain in the pods.
Maybe we can exchange seeds and try and cross the plants to see if we can develop a purple-podded, black seeded runner bean?