Runner bean pollination problem

[Bren In Pots]

Zjho I’ve found this article hope it helps.

https://scottishwildlifetrust.org.uk...hort%20tongue.

[Zjho]

All my local big bumble bees are drilling into the backs of runner bean blooms for nectar and suspect that inhibits pollination and fruiting. Not a bean from at least 100 blooms. Is there a solution, fine nets to allow smaller flies only perhaps ? Luckily dwarf beans are not effected by this habit.