I am looking for a specific post apocalypse manga, could be manhwa, about this girl in a barren world where vegetation is rare. She has a test tube, given to her by her late father, that contains seeds (or maybe flower) that she wants to take to a place her father mentioned. On her journey she meets a man that saved her life by destroying a giant robot. Once he destroys the robot it begins to sprout vegetation. It was something like that. Landscape was barren desert land, they avoid the dangerous of the land by traversing in airships and I do not recall much else.

I read a bit of it and I can no longer remember what is called and where I read it. I think it was a manga but it could have been a korean manhwa.

Sahara the Flower Samurai

Can you imagine an imaginary menagerie manager imagining managing an imaginary menagerie?

Thank you