I would like to plant seedling perennials such as shasta daisy, coneflower and black eyed susans in grow boxes for resale to nurseries and to the general public. If the soil and moisture is ideal how close can I plant them if I plant them when they are two inches tall and take them out before one full year of growth. Can they be spaced as close as 8 inches if I remove them before they reach maturity? I would like to grow them and eventually sell them in 6" pots. Would it be better to plant these perennials in a 6" pot instead of directly in the grow box soil and then bury the pots in grow box soil. This would provide for four plants per square foot and keep the roots from growing into each other. Please give me your thoughts....Gary