This is really cool! Your artstyle is great, I must say, just has that wonderful creepy atmosphere, that goes really well with the music that you made as well
I did see that you said you focused on narrative and message over gameplay, but I do think you could do something more with gameplay that would enhance that even more. This is stuff that is out of gamejam scope, but something that could be interesting if you wanted to build more on the project. I think having two things that are dropping, one that regresses the plant in addition to what you already have would make it a bit more engaging. It could also add a bit more of a mystery, for example if what regresses the plant when you're giving it bones is something like fertilizer or water, then that would make it a bit more unsettling, in a "what am I growing here?" kind of way. Maybe even have a sound effect where it cries out in pain when you give it the wrong thing.
Overall a very fun experience though, good job!