Hi Highlander, " I didn't bother saving seeds from the zinnias with only single layers of petals, only the thick doubles." We think alike on that. I don't like the single zinnias, either. In fact, since I breed zinnias as a hobby, I usually pull up single zinnias, because I don't want bees crossing them with my better zinnias. If a cull is growing too close to a zinnia that I like, I use a hand pruner to cut the cull off at ground level, so as not to disturb the nearby zinnia. "I want to grow seeds from last year's flowers so I can hopefully ensure I end up with a good assortment of colors..." I mentioned culling. One thing you can do is to plant your zinnias closer together than you normally would, and then at first bloom, remove (cull) those that aren't to your liking. Zinnias are somewhat of a numbers game, and the more of them you grow, the better are your chances of finding ones that you like. "I just can't seem to beat Murphy's law and have all of the colors from that pack represented in the same season!" One sure way to have all of the colors from that pack represented in the same season is to plant all of the seeds in the pack. If you don't have room to do that, and I assume you don't or you would have, my tip about planting them thick and thinning them out at first bloom could help you get better color diversity. "...instead of a bunch of plants that only produce a few colors because simple dumb luck resulted in growing 12 seeds that didn't include all of the 6-7 colors in the seed pack." That "6-7 colors" thing caught my eye. Zinnias come in well over a hundred different colors. There are more than 7 different pinks. Most packets of "mixed colors" are not formula mixed from fields of separate colors, but are grown in a field of mixed colors. Zinnias are pollinated by bees, which accidentally cross pollinate a significant percentage of the blooms they visit. So a lot of color mixing goes on. And even though your zinnia seed packet doesn't say anything about F1 hybrid seeds, chances are that some of them actually are F1 hybrids, courtesy of the busy bees. But bees keep poor records, so you don't know what got crossed with what. And then, when you save seeds from one of your zinnias, you actually may be saving seeds from an unlabeled F1 hybrid, so that you will get significant variation in those F2 generation hybrids that you grow next year. Adding to the variety of colors that zinnias can have, zinnias, like dahlias, can combine two or more colors in a bloom. So the number of different color combinations can be huge. You can even get green and white. Some zinnias can look somewhat like dahlias. By saving your own seeds, you can develop zinnia strains that you like, and the more zinnias you can grow, the more you will have to pick from. I grow zinnias as a hobby, and my breeding efforts look for new zinnia flower forms and plant habits. Zinnias tend to be full of surprises, so predicting the results from just a few seeds can be, as you say, subject to Murphy's Law. ZM This post was edited by zenman on Tue, Nov 18, 14 at 13:48

You'll have zinnias from sowing their seed, that much you can count on. ;) Not likely you will get exactly the same height or color range from all seedlings, they will have cross pollinated - if your plants were grown from hybrid seed, they may not have come true even if you were growing only one color. Here is a link that might be useful: Photo ripe pod and zinnia seeds

Alina and others, is "asexual method of propagation" or division difficult? Or is this method simply dividing the parent plant itself? If the last is true, I've been doing this for years whenever a plant matures and needs to be "split" or divided. Secondly, I've divided cone flowers this spring and in spite of being careful digging them and watering well, they droop in the warm spring sun for weeks till they acclimate to the change. I've turned lawn chairs upside down to shelter them from the sun. Echinacea aren't particularly happy about being transplanted! I'm thinking fall might be a better time to divide and transplant them. What are your thoughts about the best time for division/transplanting?

For some people they come up looking the same, but since they are hybrids there's a chance they turn up different.. not to mention they can cross-pollinate with other zinnias you have. Here's a link: Zinnia grow true to parent? And here's a thread on zinnia breeding, I'm sure someone in there you have your answer: It can be fun to breed your own zinnias - Part 12