the flowers are the sexual process of the plant.. and when fertilized by the bees.. will develop a pod.. at the point the flower attached to the stem ...

allow them to mature and harvest when they open naturally ..

or when you find the first one opened.. harvest the rest of the pods ... and put them in an envelope.. and let them dry and release into the envelop ... clean the seed after ..

i store seeds in z5 MI on a window sill north facing.. and curtained.. so it stays relatively cool.. compared to the rest of the heated house ... in z6.. you could probably store them in the garage .. if vermin are not an issue ... but you ought to check if they are winter hardy in z6 ... as a seed ..

ken