Saving Seeds of Zinnias
In response to a question on another thread, here's how to save the seeds of zinnias.
Wait for the zinnia flower petals to fade to brown. Deadhead the flowers on a dry day once the petals have turned brown but have not yet fallen off of the plants on their own.
If the flower heads are damp at all, hang them in a cool, dry location to dry for a few days before you remove the seeds.
When you are ready to remove the seeds, you will find the seeds located behind/beneath the base of the petals. The seeds will be brown, a little 'furry' in texture, and will look sort of like an elongated arrowhead. The size of the seed will vary, depending on which zinnia variety or varieties you have.
Remove the seeds from the flowerhead--the seeds should come off the plant easily in your hand. If they don't, they are not mature enough to save. Once you remove the seeds, spread them out to dry in a cool, dry location. Let them dry for several days. Once dry, seal them in a paper envelope or small paper bag. Next, seal that container in some sort of airtight container like a glass jar with a screw-on lid, a metal cookie tin with a lid, or a zip-lock bag. Label with the variety and date collected and then store in a cool, dry, slightly dark place where they will not be exposed to excessive cold or heat.