At this link
https://class.coursera.org/plantknows-002 you can follow a course of the university of Tel Aviv, titled: "What a Plant Knows (and other things you didn’t know about plants)"
It's predominantly about what a plant can perceive, they just started "week 2", so you can still start following it. You can follow it for free or you can pay for it and then you can receive a certicate (after a succesfull exam) for the course.
This week's about what a plant "sees", extremely interesting.
