If you live in a state that requires dispensaries to grow their own supply, you'll need a warehouse and a lot of gear. Your shopping list will include grow lights, ballasts, exhaust fans, irrigation systems, dehumidifiers, air conditioners, tables, trays, pots, plant nutrients, pesticides, soil, and of course seeds or seedlings. You may need to upgrade the power coming into the building, and if you can afford it, a backup generator if the lights go out. But getting the equipment is the easy part – any decent-sized garden supply store will have what you need. The hard part? The expertise to do it right, especially in large volumes, says Mitch Woolhiser, co-owner of Northern Lights Natural Rx.