Doraemon: Nobita and the Green Giant Legend (2008) on Netflix

Plot summary

Nobita's test papers blow away in a gust of wind, and while chasing the pages he ends up in a garbage dump, where a young withered tree has caught one of them. He takes the tree home, but his mother will not allow him to grow it in the garden. Doraemon uses a gadget that brings the tree to life, and Nobita names it Kibō, because the little creature can only say "ki". Kibō becomes part of the household, even helping Nobita's mother. Then aliens from the Planet of Green arrive to judge humanity for destroying the green on Earth, and Nobita and his friends find themselves on the aliens' planet, welcomed in the city of Green Pier.