Posted: 04/08/2017 at 16:41
It does look as though you are leaving them until they are too old before you harvest them. The main delight of grow-your-own is harvesting the products at their peak, which is far earlier than would be found in a shop.
It looks as though your beans have just run out of steam. No plant will go on producing for weeks on end.; especially if you don't feed them well.