The speaker says plants can communicate internally and with other plants to some degree.

“For the others, we don't know. For the, uh, for, uh, we don't know how complex the minds of plants are. We know that plants are able to communicate within themselves and across each other to some degree, but we don't know how smart they are, and we don't know whether they are sentient in the sense that they experience themself in the act of experience.”