I just felt compelled to share what I saw last saturday at the Bionic Garden: The Orchidarium named "Floriguay" by artist Mike Smith had a 'Big Dipper' set up solely for plants! Yes, for plants!!! A set of LED lights was used to simulate the constellation (and some fireflies) for the plants' enjoyment.
I think that the whole set up was fun and awesome. Imagine if plants actually gaze up at the stars and see constellations. Wouldn't that be amazing? You know, somewhere at the back of my mind, on some other world there exists plant-like creatures that could really see and think.
It's a perfect timing that I've been reading Vernor Vinge's "Fire Upon the Deep" in which there are sentient plants called "Skroderiders" (one of them is aptly named Greenstalk).
The Skroderiders often become lost in thought when they see spectacular landscapes which I imagine to be stars, constellations, and ringed star systems. They also are perched or riding on a contraption called 'skrodes' that enables them to move around (hence the term Skroderiders) but also contains other mechanisms that aid their memory, among other things. The skrodes were a gift to them by an advanced civilization.