Annuals Vs perennials: Do you know the difference? Annuals complete their life cycle in one season, blooming in spring and withering by autumn (like petunias or marigolds). Perennials return each The Plant Doctor: Sooty Mold Mississippi State University Extension Service PROMOTION Plant Seeds Giant Clip Venus Flytrap Seeds SeedsDay What are the differences between C3 and C4 plants in terms of photosynthetic pathways and adaptations to hot and dry environments?