I'm pretty sure it's Aster, for sure it's not milkweed or Verbena (at least the Verbenas that grow in Ohio).

Yep the offspring grow from seeds will have any varying trates in different ratios/amount of the the two parent plants. Like children know two will look exactly alike. This experimentation is how many new breeds are made. As for propagation, most nurseries and businesses do so from cuttings, as they will then be clones of the parent plant and have the exact same trates and characteristics as the parent. This is done with many plants that have problems with variation when grow from seed, such as Japanese Maples,flowering trees and shrubs etc... If on the other hand you are trying to make some new variations, find some interesting candidates and cross breed them. You never know, you could come up with the next new beautiful species. Just be careful if crossing tropical with hardy species as you might not get a plant with the hardiness desired. -Mike

Heuchera seeds are more like brown-black dust: way smaller than petunia seeds. Just sprinkle a few atop the potting mix -- avoid the temptation to use too many. And don't sprinkle any potting mix over the seeds, because they need light to germinate. But do cover the pots with clear plastic so the mix doesn't dry up. Once the seeds have sprouted, remove the cover. Mist the top or water them from below as needed.

No cilantro seeds are much smaller About the same size as a Hibiscus seed but with ribs, tan colored. Once you plant them you should end up with a few plants that will go to seed. That should give you way too many to plant the following year. They do like cool weather so here in Texas we plant them now in our early fall season. You could buy a pack of cheap seeds to plant. If they bolt then save the seeds and keep trying until you find the right planting time or check with your local extension agent for the correct time to plant in your area.