In my opinion, 3" between seeds sounds about right for the "Green Arrow" peas. For bush beans, I've always had my best results at 6" spacing between plants... but I generally plant more densely (2-3 seeds every 6") and thin to the strongest plant. This guarantees a better stand if there are germination issues, or if the soil tends to crust over after rains. If seed is in short supply and/or you don't want to thin, I would recommend about 4" between seeds for bush beans.