nice! really good concept! i'd like to play more but it's pretty intensive on the cpu xD
the art is simple but it's great. will you implement sound? tree.png
some thoughts i had on the game, i don't know exactly how did you make it, but here is how i would aproach the system
you may optimize rendering by getting rid of all the update methods, maybe a custom event system? i work with that strategy when having loads of objects
here is a video that helped me https://youtu.be/gx0Lt4tCDE0
i supose you could leave just the sprite renderer for the leaves and roots, and manage the stats on a single instance of your game manager,
that implements the update for calculating stats and/or playing animations on the leafs i don't know but i hope it helps
thank you for your game!