King Herod sought out to killed jesus as a baby. The pharisees talked about ways to kill him. And in the end, Jesus was crucified. So, even if was using plants to heal, he was still a very controversial figure. The message he was teaching was already disruptive to some of the powers or elites, and they already wanted to kill him. So I don't think Jesus would have needed to hide using plants, because he'd have died either way.