I've grown edamame - you'd probably need that specific soil inoculant for soy, it will triple the yield, which isn't that great per sq foot. You'd want to stagger your plantings, with a couple-three plants every few days, because on each plant, they all have a habit of getting ripe at once. Fresh edamame is great, but to be honest, after trying it for two summers, now I just get the frozen stuff-in-a-shell and eat that - last time I looked, it was around $1.00 a lb, and the taste wasn't that different.