Thomas made a very clever choice at that moment. Had he plucked the newly formed flower, Vreth might have grown angry. He would be able to feel the flower die, just as he always had. When men came to his Forest to chop the trees down, he felt it. When they slaughtered the animals, he felt that too. He was deeply connected to the things he brought to his land. And that did not change on the TARDIS.
"Sometimes there is no choice" Vreth replied. "I do not make choices most of the time, I follow the very nature of my being. I thrive and survive, nurture and play" he smiled softly. "But my choices, the ones I have made..." he paused. "Men have died for the choices they made in my Forest. Their power meant nothing" he said simply.
Around them, the garden continued to flourish. A variety of different coloured flowers stretched upwards and mingled together. As he smiled gently, a soft breeze tickled the grass, and the sound of distant, child like laughter could be heard on its tail. The very air tingled with natural magic and vibrant energy.