I am by no means an expert and have a simple common sense knowledge of gardening, but it works for me. Plants reproduce by way of seeds, roots and many will re-create themselves from just a section of a branch in the right environment. Lets look at flowering plants in my yard that reseed themselves and no I do not know their botanical names, all ya'll flower experts can do the identification if you like. Me, .... I call them what they look like to me.
This looks like a Zennia to me, but someone here called it a Marigold. Anyway, they can grow multi-colors on the same plant and are long lasting clipped & brought in for vase arrangements. They are beautiful in the yard and butterflies LOVE them, so if you like flowers that bring you butterflies plus can be used in cut flower arrangements this one is perfect. As the pollen is removed from the bloom, what's left will go through these stages:
Petals fall off, center mound dries and starts to separate. At this point I clip it off and spread the seeds that are inside the mound where I want them to grow, Versus letting the wind carry them away. as in this last picture.
Sometimes if I want to plant a whole bed of them I will pick the buds as the petals start to dry and put them in a little uncovered container on the porch until they are all dried and spread them in a large area all at once. I love how nature works! Oh & identifying the new sprouts is easy, just look closely at the leaves.
Full Grown
<Young plant
<Seedling
Next in this series will be my "Morning/Evening Bloomers" NO I do not know what they are really called. Stay Tuned!!