While the gameplay has a good feel to it for the most part, in the later parts (after initially arriving to the lighted tree) while still doable due to the rather simple mechanics of the game, the game fails to teach the player the objective clearly. As for the puzzle where you place rocks to make flowers grow, it feels sort of separate from the rest of the game as it only appears once in the middle while placing objects to make a path and the mushroom puzzle repeat.
You may also wish to consider letting the player skip the cutscenes of the orbs flying to the tree since for some players its frustrating to be forced out of gameplay even for what one might consider a short time.
While the game overall looks lovely, the lighting during the darker parts in the game makes it very difficult to see platforming at times. As another note, the UX elements feel slightly poorer in quality with inconsistencies and sometimes questionable placements for example having the credits with white font while there is an stone with white runes, making part of the text extremely difficult to read. This is a shame as having a less thought out UX distracts from the beautifully created environment.
Despite these points, you have done a good job in the apparent short developing time and I think the game has a lot of promise if you ever plan to take it further!