I have made this little project on control algorithms. Just click on the gardening patch and watch the magic happen! You'll see that when you click on it, you cannot go back to the first stage (the seed) without clicking the green flag and if you look inside, you will notice that the plant will grow quicker above a certain temperature and will grow slower under a certain temperature.
I'm really happy with what came out. Feel free to remix and make the plant take even longer or shorter to grow in certain states. Enjoy!