My runner beans have been fantastic this year and were last year too. I use Thompson & Morgan's Moonlight beans as I find that the sparrows pull and red flowers off the plants and Moonlight has white flowers. The beans are tasty and prolific so I would recommend you try them next year. Not much you can do now except try some tomato fertiliser. I use this mid-season and it gives them that extra boost to keep on producing flowers. Good luck!
Me too, I buy mine from Dobies in Paignton but they are the same variety. First tried them about 3 or 4 years ago and they were so good I don't bother with other varieties now. I don't use the Tomato fertiliser though, I dig a couple of deep trenches early season and empty the entire contents of one of my compost beans into it, back fill and rake to a fine tilth, then when the beans are ready for planting out I put them in there. I use 8 ft bamboo canes and when the tips reach the top of the canes I pinch the tops out to promote extra side shoot growth.