Q.Questions About Zinnias
1. How soon can you sow freshly harvested Zinnia seeds? or do I have to wait till next spring. 2. Can seeds be collected from cut Zinnia flowers once they have dried or do flowers have to be dried on the plant?
Certified GKH Gardening Expert
Seeds need to mature on the plant before they are harvested. Zinna seeds mature to black on dry flowerheads. They don't need any special cold treatment before planting the seeds, so you can plant them after harvesting if you have enough growing time left in the year before any cold spells. They are not frost hardy. Here is more: