Saving bean seed for next year
Beans are the easiest seed to save, which is why I'm starting with them. They mostly pollinate themselves, so what you save comes back the same next year, as long as you're growing one variety of each kind.
In July I tied a bit of wool round the stems of the three best plants of the climbing French bean (Cobra) and stopped picking from them. By now the pods have gone pale and papery and the beans rattle when you shake them.
Drying
I pulled the whole plants, hung them upside down in the shed for two weeks, then shelled them on the kitchen table over newspaper. They need to be dry enough that a bean shatters rather than dents when you hit it with a hammer. (Yes, I hit a bean with a hammer.)
About 200 seeds from three plants, which is far more than I need. They're in a paper envelope inside a jar with a sachet of silica gel, in the coolest cupboard in the house.
Not the runners
Runner beans cross readily with each other, and plot 13 grows a red-flowered variety right up against my fence. I might try bagging some flowers next year. This year I'll buy a packet like everyone else.