Zinnias are annual plants that bloom from spring to frost with flowers in many colors and shapes. Saving seeds from zinnias is an easy and inexpensive way to grow new plants for the next season. Seeds from hybrid zinnias will produce different-colored flowers than the parent plants, while seeds from nonhybrid zinnias will produce the same color of flowers.
Collect zinnia seeds from fully dried flowerheads from healthy plants. Use garden snips or your fingers to remove the flowerheads from the stems. A flowerhead that is ready to be harvested will "pop" when it is snapped from the stem.
Crumble the flowerheads over a piece of paper to release the seeds from the cone behind the petals, and check for attached seeds at the bases of the petals. The seeds resemble tiny arrowheads with a light coating of fuzz or fur.
Pour the seeds from 1 cup to another in front of an electric fan to separate the debris from the seeds.
Spread the seeds to dry in a cool dark place. They should be completely dry within 1 to 2 weeks.
Store the seeds in a paper bag and put the bag in a container with a lid. Add a tablespoon of silica or other desiccant to the container and close tightly. Keep in the refrigerator until you are ready to plant the seeds.