Hey fella, I have some seeds here that I have kept in a Tupperware box in a cool temp for getting on about a year now, they still pop, although some may take a little longer than others to germinate but we get there in the end, I'm sure there are some optimal conditions for long storage but I found a Tupperware sealed with tin foil wrapped round to keep them dark, has served me well over the years! I'm sure she me more expirienced guys in here will correct me if I'm wrong, but thats just my experience, hope it helps, happy growing 👍