This is a brilliant and simple idea, you created an amazing ambiance with a lot of love put into it. The music and nature sounds are such a good choice.
What this game needs is just more. More variety, more detail, more of the art, more of the same vibe, more environments, more complexity, more than what is achievable in a jam. I think a lot of people is going to appreciate the tone and feelings you've created here, and you should just give them more to do and see so they can stay for longer.
Another thing that would be an important addition is an interactive tutorial. You don't even need to use words, you can show the controls and actions gradually to the player to set the mood and tempo of the game. Show two butterflies mating and the resulting color in some way, show the caterpillar eating and hanging from a branch, stuff like that. Just make the first tutorial experience a player gets in your game have the same vibe the rest of your game has, and explaining it visually instead of literally will make it feel even more organic and relaxing.
Great work, hope to be seeing more from you!