How to preserve and plant seeds from a perennial hibiscus plant?

Why do you want to 'preserve' them? Are you moving? If you really need to preserve them you can just put the seeds (pod and all if you want) into a baggie and keep them in the fridge. I keep seeds of whatever in bags in the butter compartment of my fridge. When it's time for seeds then to form in the following seasons, take them out and sprinkle them on the ground where you want them to grow. You can cover them a bit, if you want or just let them fall to the ground. That's how they re-seed themselves naturally. I love my hibiscus and have them growing everywhere. I spread them with this method. Though I had no reason to 'preserve' them as I was just adding them to other beds in my yard. I have sent seeds home with friends and reletives from other states and they all have flowers growing from these seed starts.
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