I've heard about this before, but truly, it's amazing.
Plants communicate with each other. Scientists aren't sure yet whether the communication is intentional or a 'soliloquy,' but either way, plants talk when they are attacked by insects or animals, and other plants respond. They protect themselves and they can even protect the plant being attacked. And it's frankly amazing.
Check it out.
'Plants Talk. Plants Listen. Here's How.'
And if you found that interesting, this one is a little more in depth, and just as awesome.
Plant Talk
Here's the low-down.