A Desperate Goddess summons a hero, that turns out to be a chaotic mess of an idiot. And his best friend will babysit him to not make a bigger mess of things.

Unaware the gods has botched her summoning attempt and instead of being summoned as elves, they were turned into a cactus, and a tree. thrown into the middle of a desert, they will have to adapt to their new bodies and discover that they don't think alike anymore.

(warning this story, is partly inspired by Tree of Aeons. Go read it!)

https://www.royalroad.com/fiction/20568/tree-of-aeons-an-isekai-story