Zinnia

Zinnia elegans (Zinnia) - Planting: Sow outdoors after last frost just beneath the surface of the soil. Seeds will germinate in 5-24 days. Zinnias prefer full sun and well-drained average soil.

Seed Saving: Zinnias will cross-pollinate. Gardeners should only grow one variety at a time to save pure seed, or isolate varieties by ¼ mile. Seeds are ready to harvest when the blooms begin to turn brown and dry. The seeds are contained in the very center. When the heads are completely dry, gently crush the heads between your hand and then carefully winnow away the chaff.