The Doctor continued to play along, he was good at that "I have no idea." He said. He was looking around. He knew that they needed to make sure the flowers were all destroyed. He was confident the posion would do that.
The 11th Doctor was glad that the plan had gone well. He knew that it was good that nobody suspected them as well. "Mmm" He seemed to be quite alert to what was going on, He looked at Clara.