Hi Mugins, two sites for wild flower conservation have this to say - at the Wild Flower Society their code of conduct for the conservation and enjoyment of wild plants states that "Collecting wild flower seed for private gardening must be done sparingly and only common species should be gathered." The RHS conservation and environment policy states "The collection of seed is prohibited in the case of some rare or local species". "The RHS encourages gardeners to bear in mind conservation issues when selecting a source of wild flowers whether as seeds or flowers".
I hope that might help a little!
