5th January 1800. Alma Whittaker is born into a perfect Philadelphia winter. Her father, Henry Whittaker, is a bold and charismatic botanical explorer whose vast fortune belies his lowly beginnings as a vagrant in Sir Joseph Banks’ Kew Gardens and as a deck hand on Captain Cook’s HMS Resolution . Alma’s mother, a strict woman from an esteemed Dutch family, is conversant in five living languages (and two dead ones). An independent girl with a thirst for knowledge, it is not long before Alma comes into her own within the world of botany. But as Alma’s careful studies of moss take her deeper into the mysteries of evolution, the man she comes to love draws her in the opposite direction.