Hi! This is a semi-challenging game, I will admit. For people who are struggling: focus on the leaves and slowly growing in Spring and early Summer. When mid-Summer try to get your plant to flower and grow a slight bit more. If you feel like you're getting energy too slowly, make sure to grow a bit more leaves. (Note: If you have a lot of energy, but cannot grow branches or leaves, you probably need to grow your roots). When you can grow fruit, focus on that and leaves.
Anyway, when you get a high enough score, you go onto the next year, which is basically the same thing as restarting (new plant), but you then have to get a higher score and there are more challenges. It is confusing at first, as your plant still dies and it looks basically the same as when you fail, but the "restart" button gets replaced with a "next year" button.
I have only gotten to year three, and then I died.