Most flower seeds can easily last for a year just sitting on the shelf. If you want to store your seeds for a longer period, however, you need to prepare them for the wait. Keeping your seeds cool and free of excess humidity can easily extend their lifespan to several years, and sometimes much longer.
Place seed pods somewhere dry until the pod easily crumbles and falls away when you rub the seeds between your hands. If you can, find a spot with low light and good airflow. If your flower seeds do not have pods, skip this section.
Gently break open the pods or husks by rubbing them and drop the seeds and chaff into a bowl.
Swirl the bowl gently around several times until the small seeds drop to the bottom and the large pieces of chaff settle on top. Pick the chaff off and throw it out.
Take the bowl outside. Blow into it with enough force to blow the chaff away while swirling it around. Continue until you have blown out all the chaff, leaving the seeds in the bottom.
Storing the Seeds
Place the seeds on a clean baking pan, dish or tray and spread them out evenly. None of the seeds should be on top of each other.
Preheat an oven to 100 degrees Fahrenheit. Place the storage seeds inside the oven for six hours with the door slightly open.
Find a waterproof jar for each type of seed and place a label on it. Write the type of seed and the storage date on a piece of masking tape and stick it on the jar.
Take the seeds out of the oven and allow them to cool to room temperature. Store flower seeds in their proper jars.
Add desiccant to the jars. Pour in a teaspoon of rice or powdered milk or put in a silicone desiccant packet to keep moisture from leaking in while the seeds are in storage. Put the jars in the freezer. You should be able to store your flower seeds for at least three years without losing viability