Hi there, new to the forum! I'm starting a pretty big market garden this season and am kind of baffled by the cost of plug trays. Could I possibly use foam board (polystyrene insulation) with holes drilled in it as a sort of DIY plug tray? A farm I worked at several years ago used to use foam plug trays that they got from an old hydroponic greenhouse. I dont see any DIY write ups about making your own plugs but I was curious to hear others opinions. Thanks in advance!