This is really really good! Beautiful and perfect chill aesthetic and gameplay loop. I think the only thing I would recommend changing is the frequency you get fertiliser and water droplets. Sometimes humans ignore bunnies, and since they only drop 1 fertiliser at a time, it becomes a real waiting game and can get in the way of me wanting to populate the space with beautiful trees. At the rate I was going I couldn't expand very far because I kept losing a tree for every one I gained.
Despite that balance quirk, this is awesome and a perfect showcase of this theme in a more relaxed genre and design!