Posted: 12/08/2013 at 16:30
My daughter has the same problem (I grew all our runner beans from seed and she had 20 plants from me). She has this problem but I don't, we've picked pounds of beans & frozen some - eaten a lot!
We have put a lot of it down to birds [particularly sparrows] taking the flowers, even though we have white flowering runner beans [Moonlight from Dobies seeds in Painton, Devon]. Only difference otherwise is that I have mine in the garden soil whereas my daughter has grown them in 8 large pots + a special Bean growing bag from local GC, given a trial this year but she has kept the plants well watered so it's not about letting them dry out.