Doraemon Movie 28: Nobita to Midori no Kyojin Den

Nobita discovers a tiny sapling and, unable to plant it at home, uses one of Doraemon's gadgets to give it the ability to move and think. He names the lively little tree Ki-bou, and it quickly becomes part of the family.

Their peaceful days end when Nobita and his friends are drawn into a civilization of intelligent plants that has grown furious over humanity's destruction of nature. As Earth itself is placed in danger, Nobita's bond with Ki-bou becomes the key to showing that humans and plants do not have to remain enemies.