The Green Book — Jill Paton Walsh

Pattie and her family are among the last refugees to flee a dying Earth in an old spaceship. And when the group finally lands on the distant planet which is to be their new home, it seems that the four-year journey has been a success. But as they begin to settle this shiny new world, they discover that the colony is in serious jeopardy. Nothing on this planet is edible, and they may not be able to grow food. With supplies dwindling, Pattie and her sister decide to take the one chance that might make life possible on Shine.