David--the reason cut flowers usually will not work is the length of time they are removed from the original plant. Here I grow "garden chrysanthemums" they are hardier and a little less fancy than some of the cut ones. If I break or cut a piece off all I do is keep it in the shade, put it in potting soil that I keep continually moist. When I see it start to grow I know it started developing roots. I will baby it for awhile and eventually put it in the ground. Garden mums are perennials in my zone. Zinnias are only a long season annual. If your zinnias have roots you could try it as a watering system if I understand you correctly. I always caution try it with one because if it does not work it is not a total loss. But it could be successful for you. Everybody has a different touch with plants. Good look on pollinating your zinnias . I hope you get some neat seeds! Many joys to you!
