RANGE OF SENSES. “Plants have all the same senses as humans, and then some. In addition to hearing, taste, for example, they can sense gravity, the presence of water, or even feel that an obstruction is in the way of its roots, before coming into contact with it. Plant roots will shift direction, he says, to avoid obstacles.”
http://www.pri.org/stories/2014-01-09/new-research-plant-intelligence-may-forever-change-how-you-think-about-plants