If you've never played a "grow" game, basically they are a genre of casual games where at each turn you choose some action to perform from a small set, and the world evolves a little bit between each action. Often, you can only perform each action only once, so that the game comes down to determining what *order* to perform each of your actions, with each action affecting the environment and thus how the subsequent actions unfold.
It's a fun example of how simplifying gameplay can still lead to a fun and interesting experience.
Grow Island is a really beautifully animated, unpredictable grow game puzzle -- as much of a toy as a game. But there is an objective (a way to "win") -- get each object to its maximum level of development.
Read the review on JayIsGames
for some more context about the author and the series.