I am awaiting the arrival of many different types of seeds. I was going to try a few from each packet but would like to keep the rest around. Is there any way to store unused seeds for later. How long can I expect them to keep and still be somewhat reliable? Months? Or years? Most are different types of bonsi trees so I can only keep a few successful ones in the end. So I dont want to waste alot of started seeds. And I thought it would be an especially good idea for ME to keep some around for backup.