User blog comment:AldoHyde/The Sim's Pen - 17th January 2016/@comment-5248145-20160117050433/@comment-5248145-20160117053224

You are right that PlantSim genetics can't be "passed on" in-game without producing spores. I have been making them PlantSims when they are teens to make it a "genetic trait". And before you ask, I have a mod that allows for Sims to become PlantSims at any age while still keeping the same lifespan as other Sims. There is a reason that I wait till they are teens to change them to PlantSims rather than younger, but I don't think I will give that spoiler just yet.