Great question. I wonder this every year and have yet to harvest seeds. I hope someone has an answer that works for us!

I'll never know; my green pods fall off as well, before ripening. Just out of curiosity, I tried to winter sow those pods. Nothing germinated :(

I wonder if they weren't pollinated??

They shouldn't fall off until they turn brown and seeds fall out. Maybe they weren't pollinated. Seds are tiny and black and fall out of little ripe pods when you roll them between your fingertips.

I see the green pods and then the next day they are on the ground. It is possible that they weren't pollinated. Can I hand pollinate them by "tickling" the flower heads or do they need to be cross pollinated by another flower or variety to make seeds?

-starmoon