I love big containers but I don't love hauling them during cold season. I used to stuff the bottom with packing peanuts but if I ever replanted pots, the peanuts made a mess. These days I've found that chunky styrofoam used for appliance packing or swimming pool noodles ($1 @ $ General) are much better fillers.
First I cut a small piece of vinyl window screen ($6/roll at hardware store) and place on top of drain hole(s) to slow down soil erosion.
