Broad beans plants but few pods

I think I may have found the culprit. I was thinking the last hard frost must have affected them but today I saw a bee making holes at the base of french bean flowers and getting the nectar out without going in the flower. Hopefully this won't bee a problem for the french ones as they do it to themselves. The bee was very efficient doing it. I may have a problem growing broad beans in future if they hang around, and why wouldn't they when there is so much food for bees here compared with the surrounding grass and maize fields and verges full of bracken and nettles.