I understand about Mendel and the peas. I thought I understood about hybrids; I understand about mules. Seems there are other elements to plant heredity.
Saved seeds from my orange zinnias produced gold and pink zinnias. For a number of years, I saved seed only from pink zinnias and many turned out orange, so I started saving seed only from orange. Random colors in either case.
My formerly all-purple periwinkles are pink, white, rose, magenta and rarely purple this year? None of the red periwinkles that I planted several years ago returned any volunteer seedlings.
It's a good thing I'm usually happy with what comes up and blooms, or I'm satisfied to pull up the really non-desirables.