My broad beans are near end of life. I planted them in autumn, and now we are half way through our first summer month. Many have been blown over by strong spring winds. The bean pods are hard but most are still green, and still away from being black.

Now, the advice online seems to be that we must let the beans fully mature in the pod on the plant, and we can't save seed from opening these pods and letting them dry indoors.

What exactly is the issue? Do they go mouldy or are they just not mature enough? I'd really like to remove them now, and plant something else!