Some plants are carnivorous: they capture and eat animals. But at least one plant, a pond inhabitant called bladderwort, captures plants as well as animals. Botany One describes what they do with them. (Photo from Wikipedia.)
Plants seem to notice not just what but who is around them, and if the plant next to them is genetically close — a family member, so to speak — they might help each other out. Science magazine details how some plants grow better when planted with kin and how others avoid throwing shade on their relatives.
Can plants hear? Apparently certain flowers are listening for pollinators, and when they hear the right buzz, they sweeten their nectar to become more attractive. Read about it in the Atlantic, the New Phytologist, or the scientific article documenting the discovery.
You may know Emily Dickinson as an important poet. She also gathered, classified, and pressed all the local flowers she could into an album — 424 flowers from the Amherst, Massachusetts, region. Brain Pickings reproduces her herbarium. Some of the flowers still show their lovely colors.
Finally, Smithsonian.com ponders the puzzle of the avocado. When North American megafauna went extinct, the wild avocado should have gone extinct, too, since it depended on them for seed dispersal. Instead it managed to hang on until humans took note and domesticated it.