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Also on Skaro, a rebel Dalek with human-like qualities became fond of flowers, wearing them on its casing. When it tried to teach other Daleks that beauty had to be preserved and was a strength, the Emperor reminded them that flowers withered and died. Beauty, therefore, was not eternal or a strength and the 'diseased' Dalek was destroyed. (COMIC: Shadow of Humanity)
A species of carnivorous flower similar to poppies was native to Tiro. One caught the First Doctor and almost digested him, but he escaped by hacking at the plant's insides with his knife. (PROSE: Terror on Tiro)
On a planet, Leela investigated a giant flower which was as big as her. She fell into it just as a giant bee arrived on the scene. She climbed out of the flower after the bee left. (COMIC: The Mutants)
A vase of flowers existed in a room inside the Twelfth Doctor's confession dial. In each loop of him dying and being brought back, the Doctor tested the local atmospheric density to determine if he could escape the Veil and live by jumping out of a window. He did this by plucking a flower's petals and dropping them. (TV: Heaven Sent)